Omega Owners Forum
Omega Help Area => Omega General Help => Topic started by: dublin.jd on 07 January 2014, 23:22:28
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Hello,
Try not be sarcastic in ur reply ;D but would drilling holes in cam covers (say 1mm) or putting pressure relief valves on the covers Prevent the gaskets from leaking? 99% sure it's leaking from there.
This is my 3rd omega (y26se) that has pissed oil all over my drive in. A litre every 2 to 3 weeks. Breathers are clean now but don't want to go through all the hassle of changing gaskets again only to get 6months out of it. I change oil and filter around every 5k.
Thanks.
Ps. I have fuel trim fault code for each bank. I think oil is in plug wells or lambda wiring connector as maf is ok and vaccum pipes are intact.
Thanks again
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mmmm .. please don't take this the wrong way .. but the gaskets only leak if ...
Breathers are not cleaned properly and regularly
Pattern gaskets used
Not fitted correctly
Oil changes not done regularly with a decent (non emulsifying) oil
Mine were done when I got the car 5 years and 50,000 miles ago, and (touch wood) are still perfectly dry. However, oil changes and breather cleans done every 5000 miles.
IMHO a better solution than drilling holes ......
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Ignoring the first paragraph then...
Maf is ok? Can you explain how you know.
Air leak post maf might be next place to look?
What gaskets fitted to cam covers?
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You can't ventilate the crankcase in any way other than the factory breathers as this will cause an unmetered air leak into the intake. As said, if the breathers are kept clean, cam covers gaskets aren't unreliable.
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Yeah I'm fairly sure breathers are clean as I do them with oil change too. I haven't done the gaskets on this car yet but have done them on my previous omegas. (original Gm Opel, as I'm in Ireland) anyway I'm fed up replacing gaskets and was wondering if anyone came up with any other solutions/mods to solve this problem. Other than the norm.
I was gonna use adhesive such as tiger seal with new gaskets (original Gm of course) and drill a 1mm hole on each of the 4 covers. Or instead of the holes maybe a pressure relief valve.
Anyway I know how to do it the recommended way, just wondering if anyone has any other ideas.
Thanks for ur reply entwood, much appreciated.
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You can't ventilate the crankcase in any way other than the factory breathers as this will cause an unmetered air leak into the intake. As said, if the breathers are kept clean, cam covers gaskets aren't unreliable.
I'm not looking to ventilate crankcase, just to stop pressure blowing gaskets. A non return pressure relief valve would only let air out, it wouldn't let unmetered air leak in under negative pressure ie. Vaccum leak. I tested maf with "My Naff Code Reader". Voltages and air intake volumes seemed with in spec. I disconnected maf also. When reset the eml stays of for about 20-30 miles. But peddle trick shows fuel trim codes after about 5 miles without eml.
Again I'm not looking for the text book solution to the leaking cam cover gaskets.
Thanks again
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When you say the 'recommended way' do you mean as illustrated on this forum?
Don't be tricked into applying more sealant to the covers. This seems to have the opposite effect than you would expect.
Follow the guide on here when you do them next time :y
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Think of the solution as a back up just in case the breathers block in between cleanings.
I'm not looking for a lazy way out of cleaning breathers.
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When you say the 'recommended way' do you mean as illustrated on this forum?
Don't be tricked into applying more sealant to the covers. This seems to have the opposite effect than you would expect.
Follow the guide on here when you do them next time :y
As I said earlier, I know how to do it the illustrated way. (thanks to this site) :) I'm trying to prevent them blowing in future. Just in case I don't have time to clean them before they block. For the record I only use original parts and I clean my breathers regularly. Thanks
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The breathers keep the crank case at negative pressure, due to inlet vacuum. Don't do anything to decrease this effect or the the problem will only get worse.
I find it odd you think there's 4 covers having replaced the gaskets previously, obviously there are only two. But more importantly have the breathers been checked they actually flow air thought them? They may look clean, but are they working as designed...?
An easy check is to remove the breather pipes back of plenum and physically blow through them both ways. Only then can you be sure they are clear. The breather box behind pot 5 might be blocked?
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Further, there are numerous cars on here running with no mods to the breathers. If your isn't right then something is being missed. Drilling holes in covers will only leak more oil with cams splashing around inside.
You need to find the cause, rather than cheat and create a bigger problem.
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When I said 4 covers I meant the intake and exhaust side of each cover. Obviously 1 hole or valve on each bank would do. You knew what I meant?
And if the cam covers where under negative pressure the wouldn't blow oil everywhere. They would suck air In !
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When you say the 'recommended way' do you mean as illustrated on this forum?
Don't be tricked into applying more sealant to the covers. This seems to have the opposite effect than you would expect.
Follow the guide on here when you do them next time :y
As I said earlier, I know how to do it the illustrated way. I'm trying to prevent them blowing in future. Just in case I don't have time to clean them before they block. For the record I only use original parts and I clean my breathers regularly. Thanks
No worries mate. Just didn't want you getting caught out. Been there :'(
You will definitely need to do them now in prescribed manner so at least you know. The pipes to the rear of the plenum are easily checked visually on a regular basis too. It does sound like there may be other issues, but start with this and you can at least rule that out.
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My topic is titled "Just Curious" so let's assume I have no leak and want to find a way that it doesn't happen. Bearing in mind that service my car every time on time.
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Thanks Johnny2112, but everyone gets caught with this eventually. Sad fact of owning an omega. :)
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Thanks chrisgixer, when I clean breathers that includes breather box, plenum and throttle body. But I don't care how methodically or regularly u do that, the gaskets will eventually leak oil. They don't need to block for long to blow the gaskets and that can happen for any reason and at any time.
Anyway was just wondering if anyone has any ideas that would compliment the original breather set up and regular cleaning of the original set up
Thanks
Ps. I already know how to clean the crankcase breather assembly and associated pipes/hoses etc :) just for anyone who hasn't read previous posts.
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When I said 4 covers I meant the intake and exhaust side of each cover. Obviously 1 hole or valve on each bank would do. You knew what I meant?
And if the cam covers where under negative pressure the wouldn't blow oil everywhere. They would suck air In !
So why ARE THEY LEAKING THEN? :) why would the c case need to run at negative pressure? What about blow by gases from combustion. As Kev says, drill holes in the covers, or vent the c case, the breathers will suck extra air into the plenum, which will give you, of all things A FUEL TRIM ERROR!
Any light bulbs yet? ;) ;D
The seals don't last forever, how many miles on the 2.6. ? 80-90k on the clock and they go hard anyway.
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I'm not trying to run at negative pressure? That wouldn't make sense. It's a build up of positive pressure that makes them fail. Vaccuum is created at inlet and not the cam covers. Drilling a hole in c cover shouldn't affect vacuum. But drilling holes regardless of size wouldn't be good, I just said that to get the jist across. Pressure relief valves was more what I meant. As they only let pressure escape when it reaches a certain point(instead of the gaskets failing) a valve would not allow air in.
And yes there is 98k on my mv6 so gaskets are obviously overdue a change.
Anyway I think most people are misunderstanding what my original post was about. So let's stop going round in circles.
I appreciate all the comments,
Thanks :)
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You should be! The breathers are the only thing that remove the pressure from the crank case. By vacuum from the plenum.
Drill a hole and you introduce more air than the maf has metered. Fail.
Fit a pressure relief valve to relieve pressure, then the pressure shouldn't be there in the first place. Your breathers are blocked. Fail.
If the breathers are clear, and it still leaks, gaskets failed.
(Assuming its the cam covers leaking of course)
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I think that the OP's suggestion of a pressure relief valve is a good idea to be honest. :)
If it was mounted on the cam cover where it is easily visible and you could spot oil weeping from it then you know it's time to clean your breathers. The advantage is that you havn't blown the cam cover gaskets and saved a lot of cash and hassle! ;)
Of course no sensible Omega owner would wait for such an event and we all know that if you clean your breathers regularly then you shouldn't have a problem with the cam cover gaskets, but none of us are perfect and I'd wager that most of us have changed the gaskets at some point in our Omega ownership. :-\
So I don't think it would be a bad modification. The problem it would seem to me, would be getting a valve that would let go before the gaskets do whilst maintaining an appropriate pressure within the crankcase. :)
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I think that the OP's suggestion of a pressure relief valve is a good idea to be honest. :)
If it was mounted on the cam cover where it is easily visible and you could spot oil weeping from it then you know it's time to clean your breathers. The advantage is that you havn't blown the cam cover gaskets and saved a lot of cash and hassle! ;)
:)
Of course no sensible Omega owner would wait for such an event and we all know that if you clean your breathers regularly then you shouldn't have a problem with the cam cover gaskets, but none of us are perfect and I'd wager that most of us have changed the gaskets at some point in our Omega ownership. :-\
So I don't think it would be a bad modification. The problem it would seem to me, would be getting a valve that would let go before the gaskets do whilst maintaining an appropriate pressure within the crankcase. :)
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Finally, someone who understands what I'm trying to achieve. :) I'm not looking to bypass the breathers or avoid cleaning them. Just looking for a fail safe.
Thanks again
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Finally, someone who understands what I'm trying to achieve. :) I'm not looking to bypass the breathers or avoid cleaning them. Just looking for a fail safe.
Thanks again.
Sorry for the repeat, I made a mess of last post.
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I'm afraid I must join the "not a good idea" group on this one ....My reasons are quite simple ... under normal operating conditions, with clean breathers, the sump is kept under slight negative pressure by the vacuum effect through the breather box, this both prevents the CC gaskets "blowing" and ensures that all noxious fumes, oil vapours, blowby gases etc, are returned to the combustion chambers and burned before reaching the atmosphere.
The ONLY ways positive pressure can be achieved within the sump are either loss of vacuum or excess gas inwards. Excess gas inwards would be rapidly noticed by the loss of performance as the engine would suffer a severe loss of compression.
That just leaves loss of vacuum; again.. only two ways for this to occur, actual loss of vacuum from the engine intake; this again would also give a large loss of performance or ... AS IS THE MAJOR OCCURRENCE, blockage of the breather pipes/box that get the vacuum from the intake to the crankcase.
As there should be a negative pressure, even an equal pressure, let alone a positive pressure sufficient to blow the gaskets, is a serious fault and should be rectified, NOT masked by the fitting of relief valves to "limit" the erroneous overpressure.
IMHO the ONLY method to prevent the over pressure occurring is the correct and frequent cleaning of the breather system such that it does the job it was designed to do.
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I'm afraid I must join the "not a good idea" group on this one ....My reasons are quite simple ... under normal operating conditions, with clean breathers, the sump is kept under slight negative pressure by the vacuum effect through the breather box, this both prevents the CC gaskets "blowing" and ensures that all noxious fumes, oil vapours, blowby gases etc, are returned to the combustion chambers and burned before reaching the atmosphere.
The ONLY ways positive pressure can be achieved within the sump are either loss of vacuum or excess gas inwards. Excess gas inwards would be rapidly noticed by the loss of performance as the engine would suffer a severe loss of compression.
That just leaves loss of vacuum; again.. only two ways for this to occur, actual loss of vacuum from the engine intake; this again would also give a large loss of performance or ... AS IS THE MAJOR OCCURRENCE, blockage of the breather pipes/box that get the vacuum from the intake to the crankcase.
As there should be a negative pressure, even an equal pressure, let alone a positive pressure sufficient to blow the gaskets, is a serious fault and should be rectified, NOT masked by the fitting of relief valves to "limit" the erroneous overpressure.
IMHO the ONLY method to prevent the over pressure occurring is the correct and frequent cleaning of the breather system such that it does the job it was designed to do.
Sigh..... ::) ::) ::)
The OP never suggested neglecting cleaning his breathers or fitting something to 'mask' a problem. He's clearly (to me anyway) stated that he cleans his breathers when he services every 5000 miles. All he's suggesting is something to save the camcover gaskets should the breathers become blocked. Which in my opinion isn't a bad idea, as camcover gaskets are expensive and a PITA!
Perceived wisdom here is that you don't fit alloy cam covers and tighten them down, because then the crank seal will go instead of the cam cover gaskets if the breathers become blocked. All the OP is suggesting is creating a more convenient weak spot than the cam cover gaskets. ;)
Your last sentence is of course correct Entwood! :y :y :y
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Sir Tigger .. not going to repeat quote the whole thing as it is a tad pointless.. we can all read upwards !
BUT .. again IMHO ... if relief valves were fitted the tendency would be to rely on them ....
sort of .. "I don't need to/won't clean the breathers until the relief valve pops ..." which is inherently bad .. again IMHO
If this was such a good and practical idea, why haven't the many highly experienced engineers that frequent both here and ABS ever suggested it before ??? The engines have been around 20 years, and doing this to CC gaskets for 20 years (if neglected) ..... ???
Not being cynical or awkward .. just my take on the matter
:(
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Sometimes the simple ideas are overlooked by the cleverest, but as you say it's a bit pointless arguing about it.
I just think that most have missed the point of the OP that's all. ::)
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I appreciate everyone's comments. And we all have an opininon for and against. I feel it would benefit me personally and was hoping to get ideas from like minded people. I'm not trying to cause debate (not that there's anything wrong with debating stuff) and hopefully come out a bit wiser. Please stop telling me to keep the set up original as that's what I'd like to improve.
Sir Tigger seems to be the only one to read my post and get what I mean without explaining further.
No disrespect to any other comments.
Thanks all, again
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Sometimes the simple ideas are overlooked by the cleverest, but as you say it's a bit pointless arguing about it.
I just think that most have missed the point of the OP that's all. ::)
Quite the opposite. The op isn't listening, its a pointless exercise. But its his car, and all that. :y
You said yourself, how much pressure are we talking? And the gaskets need charging anyway. First rule of modifying anything, get it working correctly, THEN see what can be improved.
Don't start from a failed base line, thus building on a failed principle that can only lead to further .... Oh never mind. ;D
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I am listening. People are in too much of a hurry being pessimistic, instead of adding anything constructive. Lets pretend my car is perfect and I want to keep it that way, and also modify the breather aassembly. The real condition of my car is irrelevant to what I'm asking. Please stop nit picking. I'm looking for ideas, not criticism! But if it's constructive, then keep it coming. Obviously not everyone thinks it's a good idea and that's fine. I want to hear from people that agree.
Thanks
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Nice to see our normal smilies back!! :)
Anyway, I have a question (from a learning perspective, so don't shout at me or I'll get my bear stick out :o ;D)
Air is drawn in from the crankcase to the inlet manifold (via the breather system) due to the vacuum created by the pistons going down on the inlet stroke (not the power stroke as both valves are closed).
I presume then that this vacuum on the inlet stroke also acts on the components above i.e. cam covers/gaskets.
SO. Assuming I've got this correct then surely drilling holes will pull more air in from the outside via these holes thus bringing in air that's not been account for by the MAF. This would cause a lean condition, no?
Thinking about Dublin.JD's suggestion of a one way valve... as it's a vacuum and no more air can be drawn in then surely this wouldn't have any effect as the vacuum pressure would still be applied to the CC gaskets?
Again, I'm not arguing with anyone so don't take anything out on me. Just trying to get the process correct in my head :y
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I can see where the OP is coming from and to be honest i don't have a clue, suck it and see you never know you might have stumbled on something.
Just talking in general but when people say they have cleaned out the breathers what do they mean by cleaned out, is it just a case of poking something down the holes in the breather block?
The reason i ask is the breather may still be blocked and if you look inside one you'll see what i mean. A while back, sorry can't find the photos now, i removed the cover from the breather block.
If your a bit handy with the spanners then it is an easy job to do. First drill through the centre spot weld and then prize the cover off, its a bit of a job but it will come off. Once the lid is off you'll see all the years worth off crap thats inside
Once you have cleaned it all out you'll need the flatten off the spot weld stub left in the casing, drill and tap to six mm. Refit the cover using the grey sealant as used on the oil cover.
With the cover countersink the hole and use a countersunk screw as used on from brake discs. You'll need to use a countersunk screw as the cover is tight against the back of the head once refitted.
By doing this you can remove the cover from the breather box each time you want to clean it and saves pushing all that crud back down into the crank case.
Ran this setup on my car for a number of years and never had a problem with leakage
Like i said at the start give it a ago, get a couple of spare covers just in case and see what happens, your car your rules but let us all know how you get on
Cheers
Andy
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By doing this you can remove the cover from the breather box each time you want to clean it and saves pushing all that crud back down into the crank case
Makes sense to be able to access and clean the crud out :y I would normally take all the adjoining pipes off to clean too rather than poke the crap down :y
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If I'm honest, I thought there would be positive pressure in cam cover due to combustion gases getting by the piston rings (albeit in small amounts) and that the pressure builds up only when the breathers become blocked. I don't see how there could ever be negative pressure in cam covers as the intake manifold/plenum vacuum is in no way connected to the cam covers.
Maybe I'm wrong but I thought the only way pressure gets to the cam covers is through the oil passages that lube the cams and hydraulic lifters etc.
Someone can hopefully she'd light on this.
Thanks
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Thanks ANDYC for the positive/constructive post.
Thats good advice, I'll hang on to that. :)
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If I'm honest, I thought there would be positive pressure in cam cover due to combustion gases getting by the piston rings (albeit in small amounts) and that the pressure builds up only when the breathers become blocked. I don't see how there could ever be negative pressure in cam covers as the intake manifold/plenum vacuum is in no way connected to the cam covers.
Maybe I'm wrong but I thought the only way pressure gets to the cam covers is through the oil pressure, ie. Through the passages that lube the cams and hydraulic lifters etc.
Someone can hopefully she'd light on this.
Thanks
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If I'm honest, I thought there would be positive pressure in cam cover due to combustion gases getting by the piston rings (albeit in small amounts) and that the pressure builds up only when the breathers become blocked. I don't see how there could ever be negative pressure in cam covers as the intake manifold/plenum vacuum is in no way connected to the cam covers.
Maybe I'm wrong but I thought the only way pressure gets to the cam covers is through the oil passages that lube the cams and hydraulic lifters etc.
Someone can hopefully she'd light on this.
Thanks
I'm thinking that's when the piston's on it's downward inlet stroke. But again I'm not sure either :y
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Thanks Webby the Bear :)
Yeah but that's where the vacuum comes from for the brake servo and multi rams etc.
But I thought Breathers are for the crankcase, not cam cam covers. I know that if breathers are blocked pressure builds up in crankcase, and is transfered to cam cover through oil pressure. I doubt vacuum has anything to do with cam covers.
Again correct me if I'm wrong. Hopefully backing it up with info. At least i might learn something.
Thanks
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If I'm honest, I thought there would be positive pressure in cam cover due to combustion gases getting by the piston rings (albeit in small amounts) and that the pressure builds up only when the breathers become blocked. I don't see how there could ever be negative pressure in cam covers as the intake manifold/plenum vacuum is in no way connected to the cam covers.
Maybe I'm wrong but I thought the only way pressure gets to the cam covers is through the oil passages that lube the cams and hydraulic lifters etc.
Someone can hopefully she'd light on this.
Thanks
The breather bridge .. the big bit with ecotec written on it..... is connected to the plenum via the "top hat" seal (underneath) [lines 2&3 in attached picture]... so vacuum in plenum = suck in breather bridge = suck in breather pipes at the rear of the breather bridge= suck in breather box to which those pipes are attached = negative presure in crankcase to which the breather box is connected.
There are also two pipes in the breather bridge that go forward to the throttle bodies [lines 1& 4] which will also get a suction effect from the TB's
If ANY of those pipes get blocked .. and the air movement (or "suck" if you prefer) (then blockage if it occurs) comes from the breather box up into the plenum ... not the other way round ... any of those pipes, or the airways in the plenum bridge (which are a tad small) get blocked and the breather system stops working, then the pressure builds up.
(http://images.omegaowners.com/images/guides/v6_breathers/breather_assembly.jpg)
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How likely is it that the breather box itself might get blocked up? ???
So the breather pipes and the breather bridge might have been thoroughly cleaned and you think all is well, but unbeknown the box is still blocked causing the dreaded build up of pressure..... :-\
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How likely is it that the breather box itself might get blocked up? ???
So the breather pipes and the breather bridge might have been thoroughly cleaned and you think all is well, but unbeknown the box is still blocked causing the dreaded build up of pressure..... :-\
Ive had one blocked solid , just poking the crap down to clear the breather box entries wont clear what crap is in the box itself if its really bad .
(https://encrypted-tbn3.gstatic.com/images?q=tbn:ANd9GcRA_onzUh2DdwzYqzap2sG63lWSkLqnMTHsDzJXP-6hdK8PaK1w)
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How likely is it that the breather box itself might get blocked up? ???
So the breather pipes and the breather bridge might have been thoroughly cleaned and you think all is well, but unbeknown the box is still blocked causing the dreaded build up of pressure..... :-\
Ive had one blocked solid , just poking the crap down to clear the breather box entries wont clear what crap is in the box itself if its really bad .
Maybe a job to be included on a new Omega purchase then? :-\
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Entwood, thanks for taking the time to explain that so well. :) and I see what ur saying. But don't see how the pressure in the crankcase is related to the cam covers other than through oil pressure? and not vacuum.
Again I'm keeping an open mind.
Thanks
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Higher crankcase pressure forces oil out through any gaps/weakspots. The higher the crank pressure, the more oil gets forced out. Absolutely nowt to do with oil pressure :y
Blow through a straw into a full glass of water and watch what happens...
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If I'm honest, I thought there would be positive pressure in cam cover due to combustion gases getting by the piston rings (albeit in small amounts) and that the pressure builds up only when the breathers become blocked. I don't see how there could ever be negative pressure in cam covers as the intake manifold/plenum vacuum is in no way connected to the cam covers.
Maybe I'm wrong but I thought the only way pressure gets to the cam covers is through the oil passages that lube the cams and hydraulic lifters etc.
Someone can hopefully she'd light on this.
Thanks
The breather bridge .. the big bit with ecotec written on it..... is connected to the plenum via the "top hat" seal (underneath) [lines 2&3 in attached picture]... so vacuum in plenum = suck in breather bridge = suck in breather pipes at the rear of the breather bridge= suck in breather box to which those pipes are attached = negative presure in crankcase to which the breather box is connected.
There are also two pipes in the breather bridge that go forward to the throttle bodies [lines 1& 4] which will also get a suction effect from the TB's
If ANY of those pipes get blocked .. and the air movement (or "suck" if you prefer) (then blockage if it occurs) comes from the breather box up into the plenum ... not the other way round ... any of those pipes, or the airways in the plenum bridge (which are a tad small) get blocked and the breather system stops working, then the pressure builds up.
(http://images.omegaowners.com/images/guides/v6_breathers/breather_assembly.jpg)
Ok I've read all that again and came to the conclusion that adding pressure relief valves to the cam covers would be beneficial. At least til the breathers were remedied.
Does that make sense?
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Entwood, thanks for taking the time to explain that so well. :) and I see what ur saying. But don't see how the pressure in the crankcase is related to the cam covers other than through oil pressure? and not vacuum.
Again I'm keeping an open mind.
Thanks
The oil pressure in the cam covers is zero .. oil pressure ONLY exists in oil ways, drillings, pies etc .. once the oil is sprayed onto a surface, like a cam lobe, the pressure is zero.
Within the cavity that is the cam covers/crankcase there is only air pressure, this increases with the effect of gas blowby from the compression/combustion pressures leaking past the piston rings, and is decreased by the effect of the breather suction we are discussing. The actual "atmosphere" within the crankcase/cam covers cavity comprises a mix of blowby gases/oil mist/water vapour.
If the pressure builds up due to blocked breathers, we know the cam cover gaskets are the weakest link, so they fail and leak the "atmosphere" from within to without .... the blowby gases will simply escape, the water vapour will evaporate fully, the oil mist will condense and stick to any surface it can, then run and appear as a leak. If the cam cover gasket hole is large enough some of the lubricating oil spray from within may well leak out directly through that hole.
The answer is to maintain the slight negative pressure that the "vacuum" from the plenum causes via the breather system, this will "suck" the "atmosphere" out along the breather pipes until it gets burned back in the cylinders ... unfortunately for us .. the temperature change from a hot crankcase to a cold(ish) plenum cause the oilmist to condense as the horrible emulsified mess that we get, that if not cleaned out blocks the airways we want to do the job !!
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Higher crankcase pressure forces oil out through any gaps/weakspots. The higher the crank pressure, the more oil gets forced out. Absolutely nowt to do with oil pressure :y
Blow through a straw into a full glass of water and watch what happens...
How is the pressure transfered from crankcase to the cam covers? If not through the oil?
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Via the channels which drain the oil back to the sump ::)
Breather system only exists to feed crankcase fumes back into the clean side of the engine for combustion, rather than venting to atmosphere...
A new fangled idea from the mid seventies ::) deliberately venting to atmosphere might actually be illegal :-\
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Via the channels which drain the oil back to the sump ::)
Breather system only exists to feed crankcase fumes back into the clean side of the engine for combustion, rather than venting to atmosphere...
A new fangled idea from the mid seventies ::) deliberately venting to atmosphere might actually be illegal :-\
Excellent ! Can't believe I didn't think of that. ;D
I still think adding pressure relief valve would benefit, at least as a fail safe as leaking oil everywhere can't be legal either?
Thanks for the light bulb moment. :y
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Entwood, thanks for taking the time to explain that so well. :) and I see what ur saying. But don't see how the pressure in the crankcase is related to the cam covers other than through oil pressure? and not vacuum.
Again I'm keeping an open mind.
Thanks
The oil pressure in the cam covers is zero .. oil pressure ONLY exists in oil ways, drillings, pies etc .. once the oil is sprayed onto a surface, like a cam lobe, the pressure is zero.
Within the cavity that is the cam covers/crankcase there is only air pressure, this increases with the effect of gas blowby from the compression/combustion pressures leaking past the piston rings, and is decreased by the effect of the breather suction we are discussing. The actual "atmosphere" within the crankcase/cam covers cavity comprises a mix of blowby gases/oil mist/water vapour.
If the pressure builds up due to blocked breathers, we know the cam cover gaskets are the weakest link, so they fail and leak the "atmosphere" from within to without .... the blowby gases will simply escape, the water vapour will evaporate fully, the oil mist will condense and stick to any surface it can, then run and appear as a leak. If the cam cover gasket hole is large enough some of the lubricating oil spray from within may well leak out directly through that hole.
The answer is to maintain the slight negative pressure that the "vacuum" from the plenum causes via the breather system, this will "suck" the "atmosphere" out along the breather pipes until it gets burned back in the cylinders ... unfortunately for us .. the temperature change from a hot crankcase to a cold(ish) plenum cause the oilmist to condense as the horrible emulsified mess that we get, that if not cleaned out blocks the airways we want to do the job !!
Thanks to u too entwood again for going in to detail. It makes sense now after reading previous post.
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I wonder if the pressure relief valve might be as simple as drilling a small hole in the cam cover and plugging with 'goo', creating the weak spot that might save the gaskets if the breather system becomes blocked.... :-\
I guess it would take a lot of trial and error to find out. ::)
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Let's say I put Schrader valves on each cam bank and removed the inner part and then screwed dust caps on them. Say with a pin hole in each cap. Surely the engine would produce more than enough vacuum to compensate for what would be lost through the pin holes? And not cause a fuel trim problem?
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Thanks SirTigger,
That's what I'm looking for! Constructive ideas.
Thanks
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Here's an idea, a constructive one too, fix the car and run it without issue like everyone else ;D
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I still think adding pressure relief valve would benefit, at least as a fail safe as leaking oil everywhere can't be legal either?
If it's leaking onto the manifolds it's an MoT issue :-X
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Here's an idea, a constructive one too, fix the car and run it without issue like everyone else ;D
Thanks for that :P but again ur missing the point, and remember my first post? It said try not be sarcastic :D
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I still think adding pressure relief valve would benefit, at least as a fail safe as leaking oil everywhere can't be legal either?
If it's leaking onto the manifolds it's an MoT issue :-X
I can put dust caps on the valves without pin holes for the mot :y
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Here's an idea, a constructive one too, fix the car and run it without issue like everyone else ;D
Thanks for that :P but again ur missing the point, and remember my first post? It said try not be sarcastic :D
;)
Seriously though, save yourself the agro, get it working correctly, first.
One thing bothers me though. All this oil escaping, but no misfires. Usually the oil runs into the spark plug wells and destroys the ignition system. Yet there's no mention of miss fires.
Makes me wonder if the oil is escaping elsewhere. In which case, no amount of modding cam covers will be relevant, if, for example, the sump is leaking, or the oil pump, or the dip stick tube, or the oil pressure or level sensors, or the front crank seal.
Sorry but there's way too many questions unanswered as to the actual fault, to even consider weather what your suggesting will help (it won't) the faults you posted yourself.
You still haven't confirmed if the breathers are actually clear to blow through, with an airline or whatever.
Still haven't confirmed if its the cam covers leaking.
Still don't understand how the system works.
Yet still want to alter it anyway.
This is not logical captain.
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I understand how it works now thanks to the people on here.
All hoses, breathers etc are clear. I also cleaned breather box but didn't take it off and open it up. So maybe that something to do when replacing gaskets. As there's 98k on clock and nothing to suggest they've been done before.
I have no mis fire but have 0170 and 0173 fuel trim codes.
Could they be caused by leaking cam covers?
I've had other omegas, all petrol. (2 x 2.5's and now a 2.6) with leaking c covers but no fuel trim codes? (not as bad as this one though)
It's defo c covers leaking as there's oil on heads and burning oil smell due to exhaust manifold. Luckily enough there's no oil in plug wells (a first for me)
When I get around to doing the gaskets I would also like to add a fail safe just to be sure. (Obviously after I get it 100%)
That's all.
I do appreciate all the comments. :)
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Imagine someting like a one way valve on the rocker cover or covers that lets pressure out,just before the gasket blows,and triggers a warning light to warn us. ;D ;D (clean your breathers)
Think that is what the OP means..
Time to strip down the wifes pressure cooker :y
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Imagine someting like a one way valve on the rocker cover or covers that lets pressure out,just before the gasket blows,and triggers a warning light to warn us. ;D ;D (clean your breathers)
Think that is what the OP means..
Time to strip down the wifes pressure cooker :y
Thanks, I don't feel weird when other people understand what I'm saying :y
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I understand exactly where you are coming from. :y :y But what others are saying is if we do the cleaning of the breathers and reg maintanace, there is no need for a safety valve to save us giving the main dealer around £30 for gaskets that have blown cos we never bothered to maintain our car.
But yes i see what you are saying :y :y :y
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We all see what your saying, but do you see what people here are saying?
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Imagine this....All cam covers are locked down,So they cannot blow under(higher than normal) crankcase pressure.
On the cam cover (or both) if its a V thing is a valve(s) that senses the pressure.
When there is higher than normal pressure the valve trips and opens up.. it also gives us the warning light on the dash,And it also puts us in limp mode,And limits the rpm,It gives us a code...IE ( high crankcase pressure) Get off your ass and clean your breathers
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Lets simplify things a wee tad ... :)
I totally DISAGREE with those who say drilling holes etc will give an unmetered air supply etc etc ... the amount of air removed from the crankcase and injected into the plenum is controlled by the size of the airways in the breather bridge, and the top hat seal (look how small the damned holes are when you try to clean them). Also .. just remove the oil filler cap .. does the engine sudenly misfire /lose power .. yet you have a dirty great hole into the crank case, that COULD cause a huge air leak if it wanted .. what actually happens is the excess pressure takes the easy route and leaves via the oil filler, the breathers now virtually stop working.
As the crank case, both cam covers, and the oil filler are all part of the same "void" .... if you are really serious about this extra hole / relief valve idea - which again I say is not needed, however your engine and time :) - why not drill the hole / fit the valve in the oil filler cap ?? It will achieve the same result .. but when you realise it doesn't work/isn't needed .. all you have to replace is the oil filler cap .. not the cam covers ! Be a damn sight cheaper and easier !!!!!!!!
:)
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Another well explained good idea from Entwood :y instead of answering questions that weren't asked or being cynical.
Anyway I haven't decided what I'll do yet. Apart from changing gaskets and cleaning breathers.
Maybe this topic has ran its course? Someone please bury it ;D
Thanks again for all the comments.
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;D :y
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I understand exactly where you are coming from. :y :y But what others are saying is if we do the cleaning of the breathers and reg maintanace, there is no need for a safety valve to save us giving the main dealer around £30 for gaskets that have blown cos we never bothered to maintain our car.
But yes i see what you are saying :y :y :y
Last time I bought a gasket set it was about £85 and I think someone recently said they were quoted £100 odd from their local dealer!! :o These prices are for V6 though, but that's why I think it's not a bad idea to introduce a simple system to save the gaskets should the breather system get clogged and of course save the hassle of changing them which compared to other cars is a PITA!!! ::)
I agree with Entwood ( :o ) in that it's not a sensible idea to introduce an extra vent into the system, but I can't see the harm in creating a weak spot that would blow before the gaskets. :)
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Lets simplify things a wee tad ... :)
I totally DISAGREE with those who say drilling holes etc will give an unmetered air supply etc etc ... the amount of air removed from the crankcase and injected into the plenum is controlled by the size of the airways in the breather bridge, and the top hat seal (look how small the damned holes are when you try to clean them). Also .. just remove the oil filler cap .. does the engine sudenly misfire /lose power .. yet you have a dirty great hole into the crank case, that COULD cause a huge air leak if it wanted .. what actually happens is the excess pressure takes the easy route and leaves via the oil filler, the breathers now virtually stop working.
As the crank case, both cam covers, and the oil filler are all part of the same "void" .... if you are really serious about this extra hole / relief valve idea - which again I say is not needed, however your engine and time :) - why not drill the hole / fit the valve in the oil filler cap ?? It will achieve the same result .. but when you realise it doesn't work/isn't needed .. all you have to replace is the oil filler cap .. not the cam covers ! Be a damn sight cheaper and easier !!!!!!!!
:)
:y
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We all see what your saying, but do you see what people here are saying?
I totally see what others are saying.
Not everyone gets what I'm saying.
For the last time, I'm not looking for a a way to avoid regular maintenance.
I was just trying to see if anyone had any ideas on adding a fail safe.
I thought I made that clear??? Yet some people are still telling me to clean my breathers!!!!! I understand that regular maintenance should prevent problems in the first place, but that's not what I asked.
Try thinking outside the box.
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Ok, try this for out of the box thinking...
Perhaps you've replaced the gaskets with genuine GM and used the sealant where you're supposed to, and cleaned the entire breather system, yet it still leaks :-\
Maybe the covers themselves are warped... No amount if venting will sort that :-X
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Ok, try this for out of the box thinking...
Perhaps you've replaced the gaskets with genuine GM and used the sealant where you're supposed to, and cleaned the entire breather system, yet it still leaks :-\
Maybe the covers themselves are warped... No amount if venting will sort that :-X
I think it must be me, because hardly anyone else seems to understand what Dublins idea is all about....... :-\ ::) ;D
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What about vectra metal rocker cover replacements :D Thats a hornets nest ;D :P
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What about vectra metal rocker cover replacements :D Thats a hornets nest ;D :P
There's always one ;D
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I must be typing in tounges! As so far only a minority of people understand what it's all about!
Forget I have a car and try to think hypothetically. That's obviously easier said than done, going by some of the comments.
It's getting old now!
:D
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You seem to be looking for a problem that doesn't exist...
You say the car is dumping half a litre of oil on your drive every week, and that it's coming from the cam covers. Yet the plug wells are dry, the vee is dry and it's not burning off the exhaust on the way to the drive...
Call me what you want, but your camcovers are the least of your leaks... Oil pressure switch, crank seal front/rear, both sump gaskets... All likely suspects based on what you have said/suggested ::)
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The oil is leaking externally from the gaskets on the outer edges. That's why it ain't getting to plug wells. It is burning off on exhaust manifolds as I can taste the smoke at traffic lights etc. I believe the gaskets failed due to their age rather than blocked breathers as I clean them regularly.
All of that is irrelevant to why I started this thread.
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You seem to be looking for a problem that doesn't exist...
You say the car is dumping half a litre of oil on your drive every week, and that it's coming from the cam covers. Yet the plug wells are dry, the vee is dry and it's not burning off the exhaust on the way to the drive...
Call me what you want, but your camcovers are the least of your leaks... Oil pressure switch, crank seal front/rear, both sump gaskets... All likely suspects based on what you have said/suggested ::)
Just reminded me to check mine from 2 weeks a go ::)
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The oil is leaking externally from the gaskets on the outer edges. That's why it ain't getting to plug wells. It is burning off on exhaust manifolds as I can taste the smoke at traffic lights etc. I believe the gaskets failed due to their age rather than blocked breathers as I clean them regularly.
All of that is irrelevant to why I started this thread.
The plug wells are also surrounded by the gasket, its very common, if not in all cases for them to fail here to, leading to oil in the plugs. It would have to be pishing out at a serious rate to be loosing 1/2 litre a week from cam covers alone. It takes very little oil to make a big burning smell, just a few small drops, for that kind of oil consumption you have another issue that needs investigating.
With basic maintenance, genuine gaskets & sealant along with regular oil changes, should see no problems and a need for your suggested modification.
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Are you using any Oil Additives like Slick 50?, as Slick 50 in particular can start to form a bake on effect, as well as blocking breather pipes, if it starts to seep through can cause havoc with Gasket Sealant.
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No additives used. And 10w 40 semi syntethic. As I said earlier I don't know if the gaskets have ever been done and with 98k on clock they must be overdue a changing. Again I only use original GM parts.
Breathers are clean and doing what they were designed to do. Also the car drives fine, even with eml on due to the short term fuel trim codes.
I was "JUST CURIOUS" to see if anyone had ever modified the original set up or if they had any ideas.
I'm fed up repeating myself and going round in circles.
In future i'll keep my curiousity to myself, and think twice before I ask a question! ???
Thanks again to the people who took the time to offer relevant advice, whether they thought it was a good idea or not. :y
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Calm down, Im not asking you to repeat yourself, was just asking if youve put any oil additive in there!
FFS.
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Calm down, Im not asking you to repeat yourself, was just asking if youve put any oil additive in there!
FFS.
Sorry mate, that rant wasn't directed at u :) the first half of post was. :y
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No point asking questions then ignoring the answers though ;)
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Where did you get the maf btw?
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No point asking questions then ignoring the answers though ;)
No point in giving answers that don't answer the question either. ;)
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No point asking questions then ignoring the answers though ;)
No point in giving answers that don't answer the question either. ;)
But they do. Oh they so do! ;D
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I think you will be the first to modify , so guinea pig so to speak :-\
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If I wanted to test this I'd do what Entwood suggested re modifying the oil filler cap and post up results. Then there'll be no argument. :y
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If I wanted to test this I'd do what Entwood suggested re modifying the oil filler cap and post up results. Then there'll be no argument. :y
The oil cap was a good suggestion from Entwood and I reckon all it would take is to drill a hole through it and plug it with a bit of silicone. :-\
Not very scientific I know..... ::) ;D
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If I wanted to test this I'd do what Entwood suggested re modifying the oil filler cap and post up results. Then there'll be no argument. :y
The oil cap was a good suggestion from Entwood and I reckon all it would take is to drill a hole through it and plug it with a bit of silicone. :-\
Not very scientific I know..... ::) ;D
It would be scientific if you took vacuum readings before/after :)
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Just make the holes in the cam covers and tee it into the existing breather system. Lots of vehicles use the cam cover as the vent system anyway.
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Quite a few cars run with these systems and have done for years .
Catch Tank (http://www.google.co.uk/aclk?sa=l&ai=CM6jFWkDQUoX_CuaW0wWzi4GYA4jIr9sCoJmJ_DKwpqr0kAEIBRAEKAVQktLltwRgu4azg9AKoAGcsob1A8gBB6kCwpSSL7Kuuz6qBCdP0GeeyhsUr_0TObTHUmXHz6xN28EAyo8czplrDvARelilSOMzZlXABQWgBiaAB8zN-QqQBwPgErGmgsHrxvv4TA&sig=AOD64_0C1edIPuz3x9H2iqhhTr6cvY-twQ&ctype=5&rct=j&q=oil+catch+tank&ved=0CEIQww8&adurl=http://www.demon-tweeks.co.uk/Product.do%3Fmethod%3Dview%26n%3D1679%26g%3D245403%26p%3D37337%26c%3D215%26utm_source%3DGoogle%26utm_medium%3DBase%26utm_campaign%3DOil%2520Catch%2520Tanks)
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Where did you get the maf btw?
Maf is original as far as I know. If it has been changed by previous owner/s original GM part was used. I reckon my gaskets failed due to age as I clean breathers regular and are clear at the moment. Inc. Breather box.
I'll have to a spare oil cap from breakers and give it a go. Then wait another 80k til New gaskets get hard to post results. (Joke) I'll just block breathers and see if valve works ;D
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T o use a catch tank, would I need to redirect breathers away from plenum and into catch tank?
Basically bypassing plenum preventing gases going back to the intake?
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Why not use a vacuum gauge to look at manifold pressure with and without breathers connected and then again with the modified cam cover OR filler cap.
Post up results next week ;)
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If I wanted to test this I'd do what Entwood suggested re modifying the oil filler cap and post up results. Then there'll be no argument. :y
The oil cap was a good suggestion from Entwood and I reckon all it would take is to drill a hole through it and plug it with a bit of silicone. :-\
Not very scientific I know..... ::) ;D
It would be scientific if you took vacuum readings before/after :)
Ooooo you're getting a bit technical there for me Webby!! :-[ ;D
But in theory any before/after reading should be the same as my take on this is not to introduce another vent but a weaker point than the camcover gaskets that would blow if the breathers got clogged. ;) :)
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Sir Tigger that was the original point of my post but it seems that got side tracked.
A few good ideas came of it though.
When I get around to doing it I'll post results.
Thanks all
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;D
Excellent. As ST says by disconnecting breathers (thus creating the blocked breather scenario) the reading should be the same . . . This would prove either way I woulda thought ?
I,m sure someone will confirm or deny :y
If so Dublin do you have a vac gauge?
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Just had another thought!! :o :o :o
If the breathers get blocked does the pressure build up evenly throughout the engine? ???
So I may put my rudimentary pressure relief valve on the filler cap, only to find that the pressure builds up under the camcovers and they still blow.... ::) :-\
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If your looking for a one way valve why not get a couple of windscreen one way valves, T Piece and some washer pipe. You can then join each valve the either side of the tie and then run one pipe back to where even you want it
Andy
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Just had another thought!! :o :o :o
If the breathers get blocked does the pressure build up evenly throughout the engine? ???
So I may put my rudimentary pressure relief valve on the filler cap, only to find that the pressure builds up under the camcovers and they still blow.... ::) :-\
The whole crankcase/camcovers is the same "void" .. there is no way one bit can have a different pressure to the rest .. :)
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I love science. And testing :)
ST, are you taking over the white coat roles from Dublin? ;D
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Unfortunately I domy have vac gauge, but hope to get one soon.
At last the thread is going in the right direction :y
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Why not use a vacuum gauge to look at manifold pressure with and without breathers connected and then again with the modified cam cover OR filler cap.
Post up results next week ;)
Too many variables I would say. MAP is a function of thottle position and load principally. Even the difference between having the headlights on or off would be enough to skew the MAP reading.
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Interesting read.
I get what your saying too, and I think its potentially a good idea - after you've changed your gaskets that is... but you know that anyway! :y
Anyway, bear with me as this is all made up in my head, but imagine this possible scenario...
Lets assume that you have just fitted new gaskets and cleaned the breathers etc, and the leak seems to be sorted.... you have left it running on the drive for 20 mins, and all is fine.
You drive a few miles to say Tesco and back... all seems fine...
So, we conclude that the gaskets have stopped the oil leaking? yes? We also assume that the breathers are working fine (as you cleaned them remember), plus its not pressurising the crankcase and peeing oil everywhere - so they MUST be working fine...
NOW, lets say you take your car on a really hard run... flat out up steep hills etc, lots of hard breaking on bends etc... and you get back, and OH DEAR, theres oil everywhere from the rocker gaskets. So we know that either A) the gaskets didnt seal properly, or B) its pressurising again. But hang on, it cant be the gaskets as they are new, and it didnt leak when you went to Tesco, and it cant be the breathers as they are clean... or can it?...
So what do we know about the ventilation system...
All engines will pressurise the crankcase - hence the need for it to be vented (into the intake system these days)
All engines create pressure because of blow-by. Which as the engine wears, increases...
The harder and faster the engine works, the bigger the bang, and there's more of them! hence the greater the blow-by....
The breather system uses tiny pipes + holes, which limit the amount of crankcase ventilation into the intake.
So, could... and this is only a 'COULD' it be that if you add up all of the above... you exceed the amount which the standard breather system 'USED' to cope with when it was a new engine?
Just my thoughts... 8)
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An excellent point I think! Would be interested in seeing if theres a way to test it. but certainly sounds feasible imo :y
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Interesting points .. :) however, my gut reaction is .... if the amount of "blowby" due to wear was sufficient to "overcome" a correctly cleaned and working breather system, and still cause the crankcase to pressurise .... then the performance of the engine would be noticeably so poor that you'd be looking at other things ?? (and buying earplugs to mask the piston slap ?? :) )
No proof whatsoever, as said .. just a gut reaction .. :)
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So what do we know about the ventilation system...
All engines will pressurise the crankcase - hence the need for it to be vented (into the intake system these days)
All engines create pressure because of blow-by. Which as the engine wears, increases...
The harder and faster the engine works, the bigger the bang, and there's more of them! hence the greater the blow-by....
The breather system uses tiny pipes + holes, which limit the amount of crankcase ventilation into the intake.
So, could... and this is only a 'COULD' it be that if you add up all of the above... you exceed the amount which the standard breather system 'USED' to cope with when it was a new engine?
Just my thoughts... 8)
My gaskets have been fitted for about 150k, with minimal weeping, ie next to none. Engine has done nearly 263k and isn't pressurising in any way shape or form, so I really don't buy that :-\
Sorry.
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So what do we know about the ventilation system...
All engines will pressurise the crankcase - hence the need for it to be vented (into the intake system these days)
All engines create pressure because of blow-by. Which as the engine wears, increases...
The harder and faster the engine works, the bigger the bang, and there's more of them! hence the greater the blow-by....
The breather system uses tiny pipes + holes, which limit the amount of crankcase ventilation into the intake.
So, could... and this is only a 'COULD' it be that if you add up all of the above... you exceed the amount which the standard breather system 'USED' to cope with when it was a new engine?
Just my thoughts... 8)
My gaskets have been fitted for about 150k, with minimal weeping, ie next to none. Engine has done nearly 263k and isn't pressurising in any way shape or form, so I really don't buy that :-\
Sorry.
I scrapped an Omega a couple of years back for a number of reasons - one of the reasons was the engine: Oil was like tar, Needed cambelt, cam covers were leaking and it ran a bit lumpy. BUT, the decider was it had a slight rattle/tapping noise from the bottom end and the blowby was excessive. Yet, this car had only covered 84k miles.... All down to how its been looked after / serviced. Pitty really as it was a facelift (X reg i think, 2.5 GLS) in good condition (only mark was on the front bumper).
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Interesting points :) btw I haven't had time to change my rocker gaskets yet, so no point in trying to mod yet either.
Anyway I don't recall having this problem with any of my other cars (not Vauxhall) although I had a 1.6 vectra with blocked breather and never blew cam cover or crank seal.
Is it just bad design or what?
Thanks
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what a weird thread and what a great idea. the intro of seatbelts must of got the same reception here - 'just dont crash' repeated 100 times. airbags must have been laffed off the forum.
ive ordered a small prv for a fiver and will install it in the oil filler cap. releases at about 5psi which should save a gasket eventually.
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T o use a catch tank, would I need to redirect breathers away from plenum and into catch tank?
Basically bypassing plenum preventing gases going back to the intake?
And loosing any facility for the crank case to run at negative pressure. How will this help?
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Just make the holes in the cam covers and tee it into the existing breather system. Lots of vehicles use the cam cover as the vent system anyway.
They do, the ls1 has similar. However the ls1 is a pushrod design, so doesn't have two cams per bank spinning around inside splashing oil over the inside of the cam cover. If breathers are attached here, inlet vacuum will just hoover up oil from the engine and spit it out of the exhaust as smoke, and increasing oil consumption.
The location of the crank case breather box behind cylinder 5 is chosen as its a still atmosphere as far as oil splash goes.
There is a combination of air ways that lead to pre and post throttle to manage the pressure during closed and open throttle situations. These pin holes, about 1mm or so are obviously set sizes the factory made to choose vacuum levels and manage oil loss through oil vapour.
I have had a car where somebody felt the need to open up the oil hole on the breather box behind cylinder 5 by an extra 1mm or so. The oil consumption on that car was decreased by a litre a month by fitting a breather box with the standard size hole again.
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T o use a catch tank, would I need to redirect breathers away from plenum and into catch tank?
Basically bypassing plenum preventing gases going back to the intake?
And loosing any facility for the crank case to run at negative pressure. How will this help?
Do you always answer questions with a question?
I was looking for advice, not cynicism. I've already gathered that you're against the modding/improving of original set ups.
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what a weird thread and what a great idea. the intro of seatbelts must of got the same reception here - 'just dont crash' repeated 100 times. airbags must have been laffed off the forum.
ive ordered a small prv for a fiver and will install it in the oil filler cap. releases at about 5psi which should save a gasket eventually.
Thank you for getting that point across.
You're one of a few that are willing to keep an open mind. :y
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T o use a catch tank, would I need to redirect breathers away from plenum and into catch tank?
Basically bypassing plenum preventing gases going back to the intake?
And loosing any facility for the crank case to run at negative pressure. How will this help?
Do you always answer questions with a question?
I was looking for advice, not cynicism. I've already gathered that you're against the modding/improving of original set ups.
Hold up, am I in trouble for asking questions? On a forum?
Shall I quote your stroppy response from earlier? No that would be childish. ;D
Seriously now. How does it help? :)
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what a weird thread and what a great idea. the intro of seatbelts must of got the same reception here - 'just dont crash' repeated 100 times. airbags must have been laffed off the forum.
ive ordered a small prv for a fiver and will install it in the oil filler cap. releases at about 5psi which should save a gasket eventually.
Thank you for getting that point across.
You're one of a few that are willing to keep an open mind. :y
Not really a question of open or closed mindednes... If summat can be improved, great... I'll wager that fiver would have been better spent on a scratch card though :-\
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T o use a catch tank, would I need to redirect breathers away from plenum and into catch tank?
Basically bypassing plenum preventing gases going back to the intake?
And loosing any facility for the crank case to run at negative pressure. How will this help?
Do you always answer questions with a question?
I was looking for advice, not cynicism. I've already gathered that you're against the modding/improving of original set ups.
Hold up, am I in trouble for asking questions? On a forum?
Shall I quote your stroppy response from earlier? No that would be childish. ;D
Seriously now. How does it help? :)
Not at all, I'm not here to argue and bitch with anyone! And I respect/accept some of ur earlier posts.
I asked a question and u replied as if I had made a statement.
How does that help ;D
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On another note, when the breathers become blocked would the point most likely to blow not be the dipstick?
Surely it would take more pressure to blow the gaskets than to pop the dipstick?
Again I'm just guessing.
And regardless of mods, I doubt anything will stop them leaking once they get old and dry out. So either way I accept its important to change them every so often. (depending on mileage and age)
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How about changing them when they leak, regardless of age/ mileage?
Just asking, like :y
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How about changing them when they leak, regardless of age/ mileage?
Just asking, like :y
Again answering a question with a question :P
U must love going round in circles, all the while learning nothing.
Thanks for that.
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I'm sorry, to which question were you refering?
Perhaps if the question asked was clearer, it might warrant a straight answer...
If the gaskets leak, they need replacing. If replaced as per the guide and now leaking then the covers might be warped. These will then need replacing as well, and must be torqued correctly otherwise they will warp and therefore leak. Rocket science is down the hall :y
You're welcome, btw.
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I'm sorry, to which question were you refering?
Perhaps if the question asked was clearer, it might warrant a straight answer...
If the gaskets leak, they need replacing. If replaced as per the guide and now leaking then the covers might be warped. These will then need replacing as well, and must be torqued correctly otherwise they will warp and therefore leak. Rocket science is down the hall :y
You're welcome, btw.
I take it ur referring to my post at 22.12.51 ?
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Actually it is in response to your initial issue.
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Actually it is in response to your initial issue.
You still don't get the point of this thread do you Al? ::) :-\ ;D ;D ;D ;D
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Actually it is in response to your initial issue.
You still don't get the point of this thread do you Al? ::) :-\ ;D ;D ;D ;D
Apparently not ::)
I just don't see how drilling holes in summat that already leaks can possibly help solve a problem that doesn't actually exist... :-\
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Actually it is in response to your initial issue.
My bad, I apologise for that. But I thought we got passed all that. As I explained earlier, I'm not trying to prevent ever changing gaskets or maintaining my car.
For the last time, I know how and when to change gaskets and clean breather system.
Just wondering if it can be improved.
I'm not going to explain that again. So please don't be offended If I don't respond to posts that are irrelevant to what I'm asking. And I can't make my point any clearer.
Thanks
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T o use a catch tank, would I need to redirect breathers away from plenum and into catch tank?
Basically bypassing plenum preventing gases going back to the intake?
And loosing any facility for the crank case to run at negative pressure. How will this help?
Do you always answer questions with a question?
I was looking for advice, not cynicism. I've already gathered that you're against the modding/improving of original set ups.
Hold up, am I in trouble for asking questions? On a forum?
Shall I quote your stroppy response from earlier? No that would be childish. ;D
Seriously now. How does it help? :)
Not at all, I'm not here to argue and bitch with anyone! And I respect/accept some of ur earlier posts.
I asked a question and u replied as if I had made a statement.
How does that help ;D
Yes yes, very good. But again, how does removing vacuum from the crank case help ?
Why consider it, continually, against all advice? I am intrigued.
By your own rules, sarcasm etc isn't allowed. So come along, straight answer please. :)
The dip stick doesn't leak because its held in. Anyone who's checked the oil on an omega would know this.
You could, of course, fit metal vectra cam covers, but if the breathers block where will the pressure go? And no it won't make a rocket launcher out of the dip stick with the bonnet open. Which is disappointing, granted ;D
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Given that the car is properly serviced, with spotless breathers and correctly fitted genuine gaskets, with correctly placed sealant, have you considered the possibility that the covers themselves might be warped?
No amount of venting will stop them leaking if they don't sit flat on the heads.
Keep a close watch on the wind, lest your feet and legs get wet.
Fit your relief valve and report back the results. That can't be much clearer either...
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I'm looking for advice, if I knew it all I wouldn't need to be here.
If ur advice to me is that it can't be done ie. Impossible, then I don't want to know.
And I said try not be sarcastic ;D that's not a rule ;D
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I'm looking for advice, if I knew it all I wouldn't need to be here.
If ur advice to me is that it can't be done ie. Impossible, then I don't want to know.
And I said try not be sarcastic ;D that's not a rule ;D
Still haven't answered the question. ::)
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I'm looking for advice, if I knew it all I wouldn't need to be here.
If ur advice to me is that it can't be done ie. Impossible, then I don't want to know.
And I said try not be sarcastic ;D that's not a rule ;D
Still haven't answered the question. ::)
The dipstick is held in by rubber o rings. I know that
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I'm looking for advice, if I knew it all I wouldn't need to be here.
If ur advice to me is that it can't be done ie. Impossible, then I don't want to know.
And I said try not be sarcastic ;D that's not a rule ;D
Still haven't answered the question. ::)
Because I don't know.
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I'm looking for advice, if I knew it all I wouldn't need to be here.
If ur advice to me is that it can't be done ie. Impossible, then I don't want to know.
And I said try not be sarcastic ;D that's not a rule ;D
Still haven't answered the question. ::)
The dipstick is held in by rubber o rings. I know that :)
Because I don't know.
Will you accept that removing vacuum from the plenum in the crank case does NOT help?
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Given that the car is properly serviced, with spotless breathers and correctly fitted genuine gaskets, with correctly placed sealant, have you considered the possibility that the covers themselves might be warped?
No amount of venting will stop them leaking if they don't sit flat on the heads.
Keep a close watch on the wind, lest your feet and legs get wet.
Fit your relief valve and report back the results. That can't be much clearer either...
When I manage to find time I will, that's the whole point of why I want a back up.
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In fact is there ANYONE here that thinks removing vacuum from the plenum is a good idea?
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Hello,
Try not be sarcastic in ur reply ;D but would drilling holes in cam covers (say 1mm) or putting pressure relief valves on the covers Prevent the gaskets from leaking? 99% sure it's leaking from there.
This is my 3rd omega (y26se) that has pissed oil all over my drive in. A litre every 2 to 3 weeks. Breathers are clean now but don't want to go through all the hassle of changing gaskets again only to get 6months out of it. I change oil and filter around every 5k.
Thanks.
Ps. I have fuel trim fault code for each bank. I think oil is in plug wells or lambda wiring connector as maf is ok and vaccum pipes are intact.
Thanks again
To answer your question, highlighted for clarity; no it won't help, but feel free to try it.
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In fact is there ANYONE here that thinks removing vacuum from the plenum is a good idea?
When I said bypass plenum I meant just the breathers, by diverting them to catch tank. I never said remove vacuum from plenum.
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What do you think an extra hole would achieve then?
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Hello,
Try not be sarcastic in ur reply ;D but would drilling holes in cam covers (say 1mm) or putting pressure relief valves on the covers Prevent the gaskets from leaking? 99% sure it's leaking from there.
This is my 3rd omega (y26se) that has pissed oil all over my drive in. A litre every 2 to 3 weeks. Breathers are clean now but don't want to go through all the hassle of changing gaskets again only to get 6months out of it. I change oil and filter around every 5k.
Thanks.
Ps. I have fuel trim fault code for each bank. I think oil is in plug wells or lambda wiring connector as maf is ok and vaccum pipes are intact.
Thanks again
To answer your question, highlighted for clarity; no it won't help, but feel free to try it.
I've elaborated more since then and u know it. Stop nit picking and turning this into a bitchfest. :y
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What do you think an extra hole would achieve then?
Hopefully a weaker point than the gaskets in case the breathers got blocked before I got around to cleaning them.
I do a lot of cold starts (short runs) and lots of mayonnaise builds up.
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In fact is there ANYONE here that thinks removing vacuum from the plenum is a good idea?
When I said bypass plenum I meant just the breathers, by diverting them to catch tank. I never said remove vacuum from plenum.
The vacuum from the plenum, pulls the blow by gasses out of the crank case., via the breathers. The vacuum is caused by the piston down stroke of each cylinder.
If you divert the breathers to a catch tank, then they are no longer connected to the plenum. Therefor, there is no longer any vacuum from the plenum to remove the blow by gasses in the crank case, and no longer keeps the crank case at negative pressure. Therefor, diverting the breathers to a catch tank REMOVES plenum vacuum from the crank case.
Please explain how removing plenum vacuum helps? :)
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Hello,
Try not be sarcastic in ur reply ;D but would drilling holes in cam covers (say 1mm) or putting pressure relief valves on the covers Prevent the gaskets from leaking? 99% sure it's leaking from there.
This is my 3rd omega (y26se) that has pissed oil all over my drive in. A litre every 2 to 3 weeks. Breathers are clean now but don't want to go through all the hassle of changing gaskets again only to get 6months out of it. I change oil and filter around every 5k.
Thanks.
Ps. I have fuel trim fault code for each bank. I think oil is in plug wells or lambda wiring connector as maf is ok and vaccum pipes are intact.
Thanks again
To answer your question, highlighted for clarity; no it won't help, but feel free to try it.
I've elaborated more since then and u know it. Stop nit picking and turning this into a bitchfest. :y
It's just a question, we're allowed to ask questions apparently ::) ;D
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In fact is there ANYONE here that thinks removing vacuum from the plenum is a good idea?
When I said bypass plenum I meant just the breathers, by diverting them to catch tank. I never said remove vacuum from plenum.
The vacuum from the plenum, pulls the blow by gasses out of the crank case., via the breathers. The vacuum is caused by the piston down stroke of each cylinder.
If you divert the breathers to a catch tank, then they are no longer connected to the plenum. Therefor, there is no longer any vacuum from the plenum to remove the blow by gasses in the crank case, and no longer keeps the crank case at negative pressure. Therefor, diverting the breathers to a catch tank REMOVES plenum vacuum from the crank case.
Please explain how removing plenum vacuum helps? :)
I disagree , vacuum would sill be there it just wouldnt bring gases back to intake. They would go to catch tank. Obviously u would have to block where the y shaped breather connected to plenum. En lighten me if I'm wrong
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Not a bitchfest, just you're not listening... I raised the point about the covers being warped five sodding pages ago, and rereading through this entire diatribe, you have...
1. Yet to answer that point, and
2. By your own admission, not actually changed the gaskets on this car.
Answer those two points and we might actually get somewhere :-X
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In fact is there ANYONE here that thinks removing vacuum from the plenum is a good idea?
When I said bypass plenum I meant just the breathers, by diverting them to catch tank. I never said remove vacuum from plenum.
The vacuum from the plenum, pulls the blow by gasses out of the crank case., via the breathers. The vacuum is caused by the piston down stroke of each cylinder.
If you divert the breathers to a catch tank, then they are no longer connected to the plenum. Therefor, there is no longer any vacuum from the plenum to remove the blow by gasses in the crank case, and no longer keeps the crank case at negative pressure. Therefor, diverting the breathers to a catch tank REMOVES plenum vacuum from the crank case.
Please explain how removing plenum vacuum helps? :)
I disagree , vacuum would sill be there it just would bring gases back to intake. Obviously u would have to block where the y shaped breather connected to plenum. En lighten me if I'm wrong
Ah, a tee from the breather tube into a vac tank?
The vac tank would have to be sealed or the vavuum will pull air from atmosphere through the vac tank instead of the crank case, and introduce an air leak.
If sealed how will it draw air and oil vapour from the crank case instead on the plenum? Answer, it won't, obviously.
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Not a bitchfest, just you're not listening... I raised the point about the covers being warped five sodding pages ago, and rereading through this entire diatribe, you have...
1. Yet to answer that point, and
2. By your own admission, not actually changed the gaskets on this car.
Answer those two points and we might actually get somewhere :-X
I do know they're leaking, not sure if covers are warped. And as I said earlier I haven't got around to doing anything yet. Again this has nothing to do with what I'm asking.
I don't understand why u respond if u have no interest or are against what i'm trying to achieve.
I don't reply to threads unless I can add something positive.
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Actually, I miss read.
Would have to block where the y shaped breather meets the plenum. ???
That's where the vacuum comes from. ::)
Let's see if you think I'm wrong.
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In fact is there ANYONE here that thinks removing vacuum from the plenum is a good idea?
When I said bypass plenum I meant just the breathers, by diverting them to catch tank. I never said remove vacuum from plenum.
The vacuum from the plenum, pulls the blow by gasses out of the crank case., via the breathers. The vacuum is caused by the piston down stroke of each cylinder.
If you divert the breathers to a catch tank, then they are no longer connected to the plenum. Therefor, there is no longer any vacuum from the plenum to remove the blow by gasses in the crank case, and no longer keeps the crank case at negative pressure. Therefor, diverting the breathers to a catch tank REMOVES plenum vacuum from the crank case.
Please explain how removing plenum vacuum helps? :)
I disagree , vacuum would sill be there it just would bring gases back to intake. Obviously u would have to block where the y shaped breather connected to plenum. En lighten me if I'm wrong
Ah, a tee from the breather tube into a vac tank?
The vac tank would have to be sealed or the vavuum will pull air from atmosphere through the vac tank instead of the crank case, and introduce an air leak.
If sealed how will it draw air and oil vapour from the crank case instead on the plenum? Answer, it won't, obviously.
Ok then, are u saying it's impossible?
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Not a bitchfest, just you're not listening... I raised the point about the covers being warped five sodding pages ago, and rereading through this entire diatribe, you have...
1. Yet to answer that point, and
2. By your own admission, not actually changed the gaskets on this car.
Answer those two points and we might actually get somewhere :-X
I do know they're leaking, not sure if covers are warped. And as I said earlier I haven't got around to doing anything yet. Again this has nothing to do with what I'm asking.
I don't understand why u respond if u have no interest or are against what i'm trying to achieve.
I don't reply to threads unless I can add something positive.
But what your suggesting won't help, at all. Are you in management by any chance?
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Actually, I miss read.
Would have to block where the y shaped breather meets the plenum. ???
That's where the vacuum comes from. ::)
Let's see if you think I'm wrong.
I disagree again, is it not the blowback gases that force the fumes through the breathers? That's my understanding but I dont know for sure and don't just take people's words for fact. So if u can explain?
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In fact is there ANYONE here that thinks removing vacuum from the plenum is a good idea?
When I said bypass plenum I meant just the breathers, by diverting them to catch tank. I never said remove vacuum from plenum.
The vacuum from the plenum, pulls the blow by gasses out of the crank case., via the breathers. The vacuum is caused by the piston down stroke of each cylinder.
If you divert the breathers to a catch tank, then they are no longer connected to the plenum. Therefor, there is no longer any vacuum from the plenum to remove the blow by gasses in the crank case, and no longer keeps the crank case at negative pressure. Therefor, diverting the breathers to a catch tank REMOVES plenum vacuum from the crank case.
Please explain how removing plenum vacuum helps? :)
I disagree , vacuum would sill be there it just would bring gases back to intake. Obviously u would have to block where the y shaped breather connected to plenum. En lighten me if I'm wrong
Ah, a tee from the breather tube into a vac tank?
The vac tank would have to be sealed or the vavuum will pull air from atmosphere through the vac tank instead of the crank case, and introduce an air leak.
If sealed how will it draw air and oil vapour from the crank case instead on the plenum? Answer, it won't, obviously.
Ok then, are u saying it's impossible?
Via the methods you've accepted as plausible, yes. Very much so.
Plain fact is, removing the vacuum that's connected to the rank case via the breathers to the plenum, makes the matter worse.
Please. Enlighten me if I'm wrong. ::)
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When I disconnect the y pipe from plenum I get fumes blowing out, not sucking in.
Try it and you'll see. That tells me that the crankcase is under positive pressure and not vacuum.
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Actually, I miss read.
Would have to block where the y shaped breather meets the plenum. ???
That's where the vacuum comes from. ::)
Let's see if you think I'm wrong.
I disagree again, is it not the blowback gases that force the fumes through the breathers? That's my understanding but I dont know for sure and don't just take people's words for fact. So if u can explain?
Your understanding is not correct.
If the blow by gases FORCE their way to the breathers>plenum>induction to the engine etc! then they are causing THE SAME positive pressure in the crank case AND HENCE THE SEALS, such as the cam cover gaskets, cam seals, cranks seals front and rear etc etc.
The breathers, via vacuum from the plenum, turn that positive pressure into a negative pressure, there by removing the pressure in the crank case and hence the pressure on the seals that you say are leaking.
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Yeah but with the y pipe connected would the pressure not be sent through the intake as it was designed to be? To be burned again for emission control?
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When I disconnect the y pipe from plenum I get fumes blowing out, not sucking in.
Try it and you'll see. That tells me that the crankcase is under positive pressure and not vacuum.
Remove the pipes, and you have two open ends. One end to the crank case the other to the plenum.
The end from the crank case should positive/ blowing, correct.
BUT the end from the plenum should be sucking/negative. If its not, it's blocked. In fact if you've removed that pipe and the engine tick over is not affected, then they are definitely blocked.
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Not a bitchfest, just you're not listening... I raised the point about the covers being warped five sodding pages ago, and rereading through this entire diatribe, you have...
1. Yet to answer that point, and
2. By your own admission, not actually changed the gaskets on this car.
Answer those two points and we might actually get somewhere :-X
I do know they're leaking, not sure if covers are warped. And as I said earlier I haven't got around to doing anything yet. Again this has nothing to do with what I'm asking.
I don't understand why u respond if u have no interest or are against what i'm trying to achieve.
I don't reply to threads unless I can add something positive.
Your camcover gaskets are leaking, and before you fix them, you are trying to establish if there is a possible way to stop them leaking in the future.
I am all for improving things to make them last longer... in fact I have invested two sets of tyres, three sets of polybushes, two trips to Wheels In Motion specifically to find an acceptable long term solution to eliminating the need to constantly replace the vertical rear bush in the front wishbones. I am also singularly responsible for the discovery that the poly rear subframe bushes for the Monaro, not only fit the Omega, but go along way to controlling the rear end when pressing on. Again done at my own time and expense.
So don't you dare suggest that I'm not interested >:(
Rather than trying to pick holes in the advice given, how about getting off your keyboard and trying some ideas out, and reporting back with your findings, good and bad.
And by the way, the word 'YOU' has two more letters in it :-X
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Yeah but with the y pipe connected would the pressure not be sent through the intake as it was designed to be? To be burned again for emission control?
Yes, but it should be sucked out, not blown.
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If the breathers were blocked I would not have those fumes coming out of y pipe while it's disconnected?again that's my understanding.
I have tis2000 so I'll look it up on that to see if I find anything.
Also have epc3 if anyone needs part numbers.
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Yeah but with the y pipe connected would the pressure not be sent through the intake as it was designed to be? To be burned again for emission control?
Yes, but it should be sucked out, not blown.
I hear what ur saying but it defo blows out on mine? Maybe that's something I need to look at?
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If the breathers were blocked I would not have those fumes coming out of y pipe while it's disconnected?again that's my understanding.
I have tis2000 so I'll look it up on that to see if I find anything.
Also have epc3 if anyone needs part numbers.
Now is that a statement or a question? Clearly they are not blocked at the crank case end on the y pipe. But are they are blocked AT THE PLENUM END. Therefor the pressure is NOT ESCAPING INTO THE PLENUM. At all.
Look up cam covers, o rings and black goo while your there.
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There is no vacuum.
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Not a bitchfest, just you're not listening... I raised the point about the covers being warped five sodding pages ago, and rereading through this entire diatribe, you have...
1. Yet to answer that point, and
2. By your own admission, not actually changed the gaskets on this car.
Answer those two points and we might actually get somewhere :-X
I do know they're leaking, not sure if covers are warped. And as I said earlier I haven't got around to doing anything yet. Again this has nothing to do with what I'm asking.
I don't understand why u respond if u have no interest or are against what i'm trying to achieve.
I don't reply to threads unless I can add something positive.
Your camcover gaskets are leaking, and before you fix them, you are trying to establish if there is a possible way to stop them leaking in the future.
I am all for improving things to make them last longer... in fact I have invested two sets of tyres, three sets of polybushes, two trips to Wheels In Motion specifically to find an acceptable long term solution to eliminating the need to constantly replace the vertical rear bush in the front wishbones. I am also singularly responsible for the discovery that the poly rear subframe bushes for the Monaro, not only fit the Omega, but go along way to controlling the rear end when pressing on. Again done at my own time and expense.
So don't you dare suggest that I'm not interested >:(
Rather than trying to pick holes in the advice given, how about getting off your keyboard and trying some ideas out, and reporting back with your findings, good and bad.
And by the way, the word 'YOU' has two more letters in it :-X
So what do u suggest? Is it impossible what I'm trying to do? Btw I'm looking for constructive ideas before I do anything.
I'm not out to offend anyone so don't be offended.
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Not a bitchfest, just you're not listening... I raised the point about the covers being warped five sodding pages ago, and rereading through this entire diatribe, you have...
1. Yet to answer that point, and
2. By your own admission, not actually changed the gaskets on this car.
Answer those two points and we might actually get somewhere :-X
I do know they're leaking, not sure if covers are warped. And as I said earlier I haven't got around to doing anything yet. Again this has nothing to do with what I'm asking.
I don't understand why u respond if u have no interest or are against what i'm trying to achieve.
I don't reply to threads unless I can add something positive.
Your camcover gaskets are leaking, and before you fix them, you are trying to establish if there is a possible way to stop them leaking in the future.
I am all for improving things to make them last longer... in fact I have invested two sets of tyres, three sets of polybushes, two trips to Wheels In Motion specifically to find an acceptable long term solution to eliminating the need to constantly replace the vertical rear bush in the front wishbones. I am also singularly responsible for the discovery that the poly rear subframe bushes for the Monaro, not only fit the Omega, but go along way to controlling the rear end when pressing on. Again done at my own time and expense.
So don't you dare suggest that I'm not interested >:(
Rather than trying to pick holes in the advice given, how about getting off your keyboard and trying some ideas out, and reporting back with your findings, good and bad.
And by the way, the word 'YOU' has two more letters in it :-X
So what do u suggest? Is it impossible what I'm trying to do? Btw I'm looking for constructive ideas before I do anything.
I'm not out to offend anyone so don't be offended.
Your doing a bloody good job ;D
Yes, it's not possible.
Constructive idea no 1.
Understand what your dealing with before oppsing with it.
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Constructive idea no 2.
Go see if there is suction from the plenum connector nipples that are visible once the y shapes pipe is removed.(at the back of the bit with "Eco tech" written on it)
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If the breathers were blocked I would not have those fumes coming out of y pipe while it's disconnected?again that's my understanding.
I have tis2000 so I'll look it up on that to see if I find anything.
Also have epc3 if anyone needs part numbers.
Now is that a statement or a question? Clearly they are not blocked at the crank case end on the y pipe. But are they are blocked AT THE PLENUM END. Therefor the pressure is NOT ESCAPING INTO THE PLENUM. At all.
Look up cam covers, o rings and black goo while your there.
For the millionth time my breathers are clear top bottom and everywhere else. And I'm well aware how to clean them and to use genuine parts and black goo
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Your telling me that there has to be vacuum in order for the gases to get from crankcase to plenum and as far as I can see that's wrong. Crankcase pressure is created through blow by gases. Not vaccuum. The cam cover gaskets don't suck in, they blow out.
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If the breathers were blocked I would not have those fumes coming out of y pipe while it's disconnected?again that's my understanding.
I have tis2000 so I'll look it up on that to see if I find anything.
Also have epc3 if anyone needs part numbers.
Now is that a statement or a question? Clearly they are not blocked at the crank case end on the y pipe. But are they are blocked AT THE PLENUM END. Therefor the pressure is NOT ESCAPING INTO THE PLENUM. At all.
Look up cam covers, o rings and black goo while your there.
For the millionth time my breathers are clear top bottom and everywhere else. And I'm well aware how to clean them and to use genuine parts and black goo
Maybe so, but your understanding of how the breathers work is wrong. That's what we're discussing here. You asked to be corrected. Remember?
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Your telling me that there has to be vacuum in order for the gases to get from crankcase to plenum and as far as I can see that's wrong.
They have to get there by NEGATIVE pressure, or there will be oil leaks from the crank case ::)
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Your telling me that there has to be vacuum in order for the gases to get from crankcase to plenum and as far as I can see that's wrong.
They have to get there by NEGATIVE pressure, or there will be oil leaks from the crank case ::)
The negative pressure comes from intake vacuum from the plenum.
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And again, my gaskets blew due to Their age and not from blocked breathers. And in that case it doesnt matter if u have clean breathers or prv's
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Your telling me that there has to be vacuum in order for the gases to get from crankcase to plenum and as far as I can see that's wrong.
They have to get there by NEGATIVE pressure, or there will be oil leaks from the crank case ::)
The negative pressure comes from intake vacuum from the plenum.
Obviously it's the vacuum that sucks the gases to the intake. But that doesn't mean the crankcase is under negative pressure.
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And again, my gaskets blew due to Their age and not from blocked breathers. And in that case it doesnt matter if u have clean breathers or prv's
Yes we know. But what's prv's...?
But again, we're discussing your understanding of how the breathers work.
Vacuum is the key, not pressure. Pressure is bad. Veeeery baaaaad.
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Your telling me that there has to be vacuum in order for the gases to get from crankcase to plenum and as far as I can see that's wrong.
They have to get there by NEGATIVE pressure, or there will be oil leaks from the crank case ::)
Obviously it's the vacuum that sucks the gases to the intake. But that doesn't mean the crankcase is under negative pressure.
The negative pressure comes from intake vacuum from the plenum.
Oh its obvious now is it? I thought it might be ;D
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Your telling me that there has to be vacuum in order for the gases to get from crankcase to plenum and as far as I can see that's wrong. Crankcase pressure is created through blow by gases.
And the vacuum is created by the large breather pipe, with the Y in it, being connected directly to the throttle body. That's a 2cm2 hose from the crankcase to the intake. Your camcovers leak because either the covers themselves are warped, the gaskets aren't fitted correctly or they have simply perished.
The oil is under pressure from the oil pump rather than crankcase air pressure, which is always NEGATIVE when the engine is running. Find a way to stop limit oil pressure under the cam covers and you'll stop them leaking, but not before the camshafts seize.
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Would negative pressur in crankcase not suck more blow by gases in, therefore affecting performance?
Again just a question. It makes more sense to me for it to be at equal/atmospheric pressure.
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Your telling me that there has to be vacuum in order for the gases to get from crankcase to plenum and as far as I can see that's wrong.
They have to get there by NEGATIVE pressure, or there will be oil leaks from the crank case ::)
Obviously it's the vacuum that sucks the gases to the intake. But that doesn't mean the crankcase is under negative pressure.
The negative pressure comes from intake vacuum from the plenum.
Oh its obvious now is it? I thought it might be ;D
Read my earlier posts, I've always had that view.
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Constructive idea, remember that?
Understand your problem first. Then worry about meddling.
First thing to do then is gets done vacuum gauges and see where the pressures are.
But your wrong. Read my eatlier posts. That's always been my view. :)
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Anyway I'm off to bed, hopefully I can sleep after the ridiculing I've just underwent! (joke) ;D
Thanks
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Your welcome. ;)
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Anyway I'm off to bed, hopefully I can sleep after the ridiculing I've just underwent! (joke) ;D
Thanks
Remember I said to pretend that my car was running as designed? Ie. Perfect!
Some people can't get passed that. And that narrows their train of thought and we all get nowhere.
Anyway I'll be back 2moro for more abuse ;D good night
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Should actually be minimal pressure in the crank case, certainly what air is in there will move around as the cylinders rise and fall, but there are six of them and as at any one moment an equal number are moving in opposite directions the air will simply move around :y
Any significant blow by will be apparent from a lack of compression and/or noise from badly worn components.
Factor in the direct connection to the air intake, and it becomes almost impossible for the crank case to have anything other than negative pressure...
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Would negative pressur in crankcase not suck more blow by gases in, therefore affecting performance?
Again just a question. It makes more sense to me for it to be at equal/atmospheric pressure.
Assuming the car is running as designed. No issues.
Also assume that crank cases should run at atmospheric pressure as you say
Now disconnect the breathers. The crank case can not possibly now be at the desired pressure. Can it!
Dear god. Can I have some strength please. ::)
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Try this...
(http://i1277.photobucket.com/albums/y486/05omegav6/IMG_20140123_011409_zpsgmydfrip.jpg)
:y
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im actually a bit shocked by this thread. its like some feeding frenzy in a nature program. lords and barons ganging up on a junior. some people should be ashamed.
ive not read all of the huge number of posts since i last posted ITS TOO BORING but there is a lot of crap being spoken here. crankcase will be under positive pressure that is why there is a breather system. as mentioned just open the oil filler cap and feel it with your hand. anyway a prv valve would not let air in it only opens to release pressure thats why its called a pressure relief VALVE. so why keep asking if the op wants to let air in his system he doesnt. some one said 5 quid on a prv would be better spent on a scratch card. yes if it was a winning card. no if at some point in the cars life if your theories about blocked breathers being the cause are correct the gaskets will leak due to crankcase air pressure pushing oil thru. how much does that cost to fix? if a prv is fitted the pressure will be vented through the oil filler cap and the gasket will be saved giving u time to clean the breathers. you'll know they need doing cos there will be stains on the bright yellow by the prv exit.
Type the letters shown in the picture:
How many road wheels are fitted to the car (digit, not spelled out)?:
What colour is the indicator on European cars, also a fruit?:
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If some people are that appalled perhaps they shouldn't join in in the exact same vain. ;)
Just saying.
They guy has changed his theory half a dozen times and displays the exact same sarcasm nobody else is allowed.
Anyway, your telling me there's no vacuum from the plenum is that correct? How does the intake air get into the cylinders then I wonder.
6,500 rpm to tickover and there is no vacuum in the plenum? Do I understand you correctly?
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Was just trying to find my copy of the Vauxhall College guide to the Omega... must be in the garage :-\
Replies 12 and 13 here are noteworthy...
http://oldsite.omegaowners.com//forum/YaBB.pl?num=1306257481/all (http://oldsite.omegaowners.com//forum/YaBB.pl?num=1306257481/all)
And this should debunk a few myths as well...
http://www.google.co.uk/url?sa=t&rct=j&q=y32se%20breather%20system&source=web&cd=2&ved=0CCsQFjAB&url=http%3A%2F%2Fwww.106rallye.co.uk%2Fmembers%2Fdynofiend%2Fbreathersystems.pdf&ei=GHTgUoOfN5T20gXW8oGoBg&usg=AFQjCNEAeZemBNjN0wzVncL9rfHuh3U2dw&bvm=bv.59568121,d.d2k (http://www.google.co.uk/url?sa=t&rct=j&q=y32se%20breather%20system&source=web&cd=2&ved=0CCsQFjAB&url=http%3A%2F%2Fwww.106rallye.co.uk%2Fmembers%2Fdynofiend%2Fbreathersystems.pdf&ei=GHTgUoOfN5T20gXW8oGoBg&usg=AFQjCNEAeZemBNjN0wzVncL9rfHuh3U2dw&bvm=bv.59568121,d.d2k) :y
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6,500 rpm to tickover and there is no vacuum in the plenum? Do I understand you correctly?
no you dont understand me read my post "crankcase will be under positive pressure". read the taxi experts article on blow by.
now youve got me wrestling with pigs. im not going to argue stupid points like is there a vacuum in the plenum THE CRANKCASE WILL BE UNDER POSITIVE PRESSURE. look it up or just stick your mouth over the oil filler and get someone to rev the car. in gear. forward preferred but reverse will do.
Type the letters shown in the picture:
What do the letters OOF (our forums initials) stand for? See image at top left of page.:
What colour is the indicator on European cars, also a fruit?:
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ah at least i am not getting that stupid
Type the letters shown in the picture:
What do the letters OOF (our forums initials) stand for? See image at top left of page.:
What colour is the indicator on European cars, also a fruit?:
any more thank you at least for that.
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It cirtainly will be if the breathers are disconnected. ;)
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Simple laws of physics now .... how can any system connected to a correctly working vacuum source (breather system) be considered to be "under positive pressure" ??
The whole crankcase is one "void".. it does not have compartments at differing pressures. It is a "sealed" void by the oil filler cap (look at the seals on the cap) and the dip stick (again, look at at the seals on the dip stick) and all the other seals/gaskets and goo.
The breather system extracts air and holds the "void" at a slight negative pressure - WHILE THE VOID IS SEALED - if you then remove the oil filler the void is no longer sealed, the negative pressure disappears (the breather system cannot evacuate the earths atmosphere) and any blowby gases, or the movement of the cylinders, will cause air movement through the bloody big hole that is the oil filler cap.
fluid laws/theory are extremely simple .. until you try and get a fluid to push against nothing .. which it cannot do ... gas (and any other fluid) can ONLY have pressure in a SEALED system.... but a vacuum can suck in a non-sealed system ... exactly as your hoover works !! it moves air by creating a vacuum (that is rapidly filled) ..... and that's what the breathers do ... they "hoover" the crank case .....
If the void is sealed, but the vacuum is not present, then with the engine running a positive pressure will build up, that is what blows the gaskets.
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this is just getting mad
so its a vacuum until you open the oil filler cap then it miraculously becomes positive pressure? and it has a fancy name, fluid theory. perhaps its like that cat in the box you never know what it is until you open the filler cap. schrodingers crankcase.
there is no vacuum anywhere on an omega unless you left your coffee flask in the boot. correction there is one on a tiny number of migs, its a few cm under the roof and 1m above the drivers seat. only on the noisy ones though.
instead there is slightly above normal air pressure in the crankcase and slightly below in the air intake. the breather connects these two. im not posting on this again it has changed from boring to irritating and boring at the same time.
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Good, now can we get on!
There's are numerous uses for vacuum on the omega. ALL of which use the vacuum in the plenum.
1) Servo assisted brakes.
Runs of the black pipe that exits the right side of the plenum, curves round the back under the breather tubes and attaches to the brake servo. I know this is vacuum operated because if/when the clip that holds it to the ac pipe wears through it, it causes an air leak/hissing/poor tick over/maf error code. Plus my brakes work with an assisted pedal. You may have noticed this, although maybe not.
2) multi rams.
Waisting my breath here for the hard of understanding but the multi rams are vacuum
Operated from the t to brake pipes at the back of the engine on the v6.
3) breathers. (Sigh)
Runs off the same lump of engine as the brake servo and multi rams. (So there is defo vacuum, right? ;D )
4) the inlet plenum to the engine
6 pistons (or 4 for effeminate types ;) )pumping up and down. The down stroke is a vacuum or no fuel air mixture would get in there, it's basic principal of the combustion engine. Times this by 6 and you have enough vacuum to feed a 3litre engine, brake servo/multi rams/breathers.
It's also enough to draw in enough air to throw maf and fuel trim errors if there is a leak from a split breather pipe to plenum as I often see on my drive when members have issues with grumpy tick over and fault codes.
Now, it's almost 2pm which means its day time. If your the type to then deliberately post up that it's actually night time where I am,or that there is no vacuum on the omega, then go ahead. ;D
Because anything under normal atmospheric pressure, is indeed a vacuum. However slight. :)
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Because anything under normal atmospheric pressure, is indeed a vacuum. However slight. :)
vacuum
ˈvakjʊəm/
noun
noun: vacuum; plural noun: vacua; plural noun: vacuums
1.
a space entirely devoid of matter.
synonyms: empty space, emptiness, void, nothingness, vacuity, vacancy;
2.
a vacuum cleaner.
synonyms: vacuum cleaner;
verb
verb: vacuum; 3rd person present: vacuums; past tense: vacuumed; past participle: vacuumed; gerund or present participle: vacuuming
1.
clean with a vacuum cleaner.
"the room needs to be vacuumed"
synonyms: vacuum-clean;
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Getting warmer ::) ;D
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There's also two vac tanks, that service the multi rams. One on the back if the inlets, tother behind the pollen filter housing.
Yes. Two. ;)
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this is just getting mad
so its a vacuum until you open the oil filler cap then it miraculously becomes positive pressure? and it has a fancy name, fluid theory. perhaps its like that cat in the box you never know what it is until you open the filler cap. schrodingers crankcase.
there is no vacuum anywhere on an omega unless you left your coffee flask in the boot. correction there is one on a tiny number of migs, its a few cm under the roof and 1m above the drivers seat. only on the noisy ones though.
instead there is slightly above normal air pressure in the crankcase and slightly below in the air intake. the breather connects these two. im not posting on this again it has changed from boring to irritating and boring at the same time.
May I suggest that instead of making stupid comments, you actually THINK about what you type ??
I'm grateful you're not going to post in this thread again as we can actually have sensible conversations that way.
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I'm gonna agree to disagree until I get around to testing all these theories.
I'll be back with results and hopefully videos as soon as I find time.
Thanks
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I'm gonna agree to disagree until I get around to testing all these theories.
I'll be back with results and hopefully videos as soon as I find time.
Thanks
I look forward to the results :y, good luck.
However, much of the advice given is based on personal experience, and the one known working solution is clear breathers and replacement GM gaskets and O rings, which as they go hard, tend to become a less effective seal.
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I'm gonna agree to disagree until I get around to testing all these theories.
I'll be back with results and hopefully videos as soon as I find time.
Thanks
Who for? ;D
;)
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LOL everyone be normal ::)
Dublin is going to test these theories. Let's discuss the results then.
One thing i want to know though....... what tests can he perform? i suggested vacuum gauge but i think someone said thats not appropriate. :-\
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LOL everyone be normal ::)
Dublin is going to test these theories. Let's discuss the results then.
One thing i want to know though....... what tests can he perform? i suggested vacuum gauge but i think someone said thats not appropriate. :-\
The tests I would wish to see results of are ...
1. Absolute air pressure in the crankcase with the void sealed and the breathers fully cleaned
2. Absolute air pressure in the crankcase with the void sealed and the breathers fully blocked
3. Absolute air pressure in the crankcase with leaking cam covers, (all other aspects of void sealing being normal), and the breathers fully blocked.
This would indicate the (1) system under normal operation (2) The pressure the system will, potentially, build to before doing damage to cam cover seals and (3) the stabilised pressure once the cam cover seals fail and leak.
I would expect (1) to be below atmospheric (partial vacuum) and (2) & (3) to be above atmospheric (positive pressure).
If the "idea" of some PRV is still the target, the value of the relief would have to be well below (2) and probably below (3) for best operation ... although, as previously stated, I don't believe it is necessary.
There is no point in doing any tests where the void is not sealed as designed.. :)
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Well put Entwood. :)
Cracking thread this! 8) A lot of hot air, vacuous opinions and full of misunderstandings! :D
Very entertaining and highly recommended!! :y :y :y
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LOL everyone be normal ::)
Dublin is going to test these theories. Let's discuss the results then.
One thing i want to know though....... what tests can he perform? i suggested vacuum gauge but i think someone said thats not appropriate. :-\
The tests I would wish to see results of are ...
1. Absolute air pressure in the crankcase with the void sealed and the breathers fully cleaned
2. Absolute air pressure in the crankcase with the void sealed and the breathers fully blocked
3. Absolute air pressure in the crankcase with leaking cam covers, (all other aspects of void sealing being normal), and the breathers fully blocked.
This would indicate the (1) system under normal operation (2) The pressure the system will, potentially, build to before doing damage to cam cover seals and (3) the stabilised pressure once the cam cover seals fail and leak.
I would expect (1) to be below atmospheric (partial vacuum) and (2) & (3) to be above atmospheric (positive pressure).
If the "idea" of some PRV is still the target, the value of the relief would have to be well below (2) and probably below (3) for best operation ... although, as previously stated, I don't believe it is necessary.
There is no point in doing any tests where the void is not sealed as designed.. :)
That's a good starting point, thanks.
I take it that u need a vac gauge to perform said tests?
I will test before I change gaskets although my breathers are clear. I will then simulate blockage and test also.
Don't think I'd go as far to simulate blockage after I change them. (might do it for 30 seconds or so and take reading)
Thanks again for giving me a starting point, in a non critical way. :y
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Well put Entwood. :)
Cracking thread this! 8) A lot of hot air, vacuous opinions and full of misunderstandings! :D
Very entertaining and highly recommended!! :y :y :y
Lots and lots of misunderstandings, none by me of course ;D
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I'm gonna agree to disagree until I get around to testing all these theories.
I'll be back with results and hopefully videos as soon as I find time.
Thanks
I look forward to the results :y, good luck.
However, much of the advice given is based on personal experience, and the one known working solution is clear breathers and replacement GM gaskets and O rings, which as they go hard, tend to become a less effective seal.
Thanks.
I understand lots of people are speaking from experience but sometimes I need to find out for myself. Especially when I don't agree with what they say. Sometimes due to them not giving proper explaination of why their theory is so and sometimes me having to see to believe. But I do take on board what people say and will question it if it doesn't make sense to me.
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Darn! Admin error. Noooo! We don't want this topic sticky. :o
::)
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LOL everyone be normal ::)
Dublin is going to test these theories. Let's discuss the results then.
One thing i want to know though....... what tests can he perform? i suggested vacuum gauge but i think someone said thats not appropriate. :-\
The tests I would wish to see results of are ...
1. Absolute air pressure in the crankcase with the void sealed and the breathers fully cleaned
2. Absolute air pressure in the crankcase with the void sealed and the breathers fully blocked
3. Absolute air pressure in the crankcase with leaking cam covers, (all other aspects of void sealing being normal), and the breathers fully blocked.
This would indicate the (1) system under normal operation (2) The pressure the system will, potentially, build to before doing damage to cam cover seals and (3) the stabilised pressure once the cam cover seals fail and leak.
I would expect (1) to be below atmospheric (partial vacuum) and (2) & (3) to be above atmospheric (positive pressure).
If the "idea" of some PRV is still the target, the value of the relief would have to be well below (2) and probably below (3) for best operation ... although, as previously stated, I don't believe it is necessary.
There is no point in doing any tests where the void is not sealed as designed.. :)
Agree 100% ...
Would also be interesting to see the results at different load/throttle too!