Omega Owners Forum
Omega Help Area => Omega General Help => Topic started by: sotmh on 14 May 2011, 23:12:37
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After a break I'm back to this off on off on project.
If anyone can help, I am a bit confused. In reading Haynes it instructs to turn crank shaft backwards 60 degrees ( 4 teeth movement) before removing timing belt.
Surely after doing this, to get TDC prior to removing timing belt, crank shaft will have to be turned again and therefore TDC is lost.
Secondly it also says to ensure to line up crank shaft timing mark with mark on oil pump as shown in illustration, but it appears this does not match picture.
Any ideas?
All assist will be greatly appreciated. :y
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I think the source of your confusion is this: if you were just changing the timing belt (kit) you'd want to get the engine to TDC, all the marks lined up, then lock everything there while belt and rest of kit is changed.
If, on the other hand, you're removing the head, you want to minimise the chances of knackering anything during removal/replacement of the head, hence the 60° backward crank rotation, to keep all pistons down a bit, away from unsynchronised valves.
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Thanks Abiton, 2nd comment is accurate, as I am planning to remove head to get it examined by engineers and have any work carried out on it.
In thinking about it, it makes sense about getting bdc.
So, from reading this, after getting bdc I can remove timing belt?
My method of counting 4 teeth movemnt is to use timing cover mark and count as required as I turn crank shaft bolt anti-clockwise. Is that ok or is there a more accuratte method.
Many thanks in advance for assist. :y
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have come across a few fidly and awkward things and with the time available to me job has taken a lot longer.
However, the only thing thats giving me a prob at moment is getting to remove mounting plate where dis module sits. module has been removed but cant see whats holding it onto head and therefore cant remove.
Any ideas please :question
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I assume the head is still on the engine, otherwise you'd be able to see easily.
You don't need to remove this lump before taking the head off, in fact you don't need to remove DIS or EGR either.
You 'just' need to detach the coolant hose from it, the purge valve (thingy on the right of the DIS in the image below) vac pipes and electrical connector, and the EGR vac pipe and electrical connector, and the DIS multiplug, and the temperature sender connections.
The lump is held onto the head by three male-torx-head bolts, two of one size, and one smaller, for some reason. you can see where these bolts were in this image:
(http://images.omegaowners.com/images/guides/2.2_useful_pics/Tempsenders_resize.jpg)
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Great and thanks Abiton. I had removed the top centre bolt and felt others at the time but not sure what they were as working blind(pic helped greatly).
Was able to remove head last night and found bores ok but top of pistons and flats of valves totally and utterly filthy or as if burnt. Is this a huge problem i.e. with pistons and therefore need changing or is there a way to clean :question :'(.
Any work on head will possibly require new valves, but don't fancy forking out for new pistons.
Any thoughts chaps to resolve
Thanks
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Got a camera? Impossible to say much about condition without good pictures.
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yes. But don't think I have correct bit to connect to computer/laptop, however will try.
I had originally planned to take progress pics to upload and thats when found I would not be able to.
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Took head to be tested. Requires skimming and a small welding. However on enquiry about condition on top of pistons, carbons seems to have burnt and caked piston tops. have been advised rings may require changing.
I now need to remove sump to access pistons for removal but obstructed by cross member. haynes says after unloosening bolts a hoist is required to lift engine to gain access to bolts hidden.
Problem is that I don't have a crane/hoist. Can't undo bolts as rusted fast. Is there another way around this prob.
Also is the engineers assesment right :question.
Also he says seals have hardened so will require replacing. Was wondering if this will cure small amount of black smoke witnessed. :-/
Have been quoted 160 for all jobs including labour and cleaning head.
Me thinks Very good price.
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I'd say to take the ring replacement thing with a pinch of salt. Others may disagree, but I've not heard much mention on here of trouble with piston rings on these engines, more likely the carbon coating has come from above rather than oil coming past the rings upwards.
Get Henry the Hoover and a hard plastic scraper on the job, and scrape-and-suck simultaneously on each piston-crown so that as the debris comes away, it goes straight up the hoover rather than down the edges. Half an hour of careful work, job done.
If he's referring to the valve stem seals, which I suspect he is, then replacement of those is a very good idea. If you are currently using/burning some oil, it will very likely reduce this to near nothing.
Wish I'd done these on ours when I had the head off. ::)
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I'd say to take the ring replacement thing with a pinch of salt.
I agree. I think he's looking to create work for himself.
The question is: how was the car running before the head came off? If it was OK and not burning oil / smoking and the mileage isn't galactic (150-200k+) the bottom end will be fine.
Kevin
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... and the mileage isn't galactic (150-200k+) .....
Bugger! :-? Mine is in that catagory! ;D ;D
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Thanks all for your reply. :y
Car was running fine although i did see some small amount of black smoke in exhaust. Mileage appx 95k. it was mentioned at the garage it may be burning oil. I'm hoping this is caused by valve stem seals and therefore once changed it will cure prob. :y
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Thanks all for your reply. :y
Car was running fine although i did see some small amount of black smoke in exhaust. Mileage appx 95k. it was mentioned at the garage it may be burning oil. I'm hoping this is caused by valve stem seals and therefore once changed it will cure prob. :y
At 95K it will be fine. :y
Stem seals are a more likely reason for oil burning but there will always be a layer of carbon on the piston crowns. Not a cause for concern, IMHO.
Kevin
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Thanks ken.
The burnt carbon appears quite extensive. Think of extremely burnt toast and you got the picture.
Tested to see how bad this was and now believe scraper only way to go. Have a gasket scraper but will have to be very carefull, or as advised may have to get a plastic scraper/spatula to do job to prevent damaging crowns
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Thanks ken.
The burnt carbon appears quite extensive. Think of extremely burnt toast and you got the picture.
Tested to see how bad this was and now believe scraper only way to go. Have a gasket scraper but will have to be very carefull, or as advised may have to get a plastic scraper/spatula to do job to prevent damaging crowns
Put a bit of grease round the edge of the piston to block the gap and prevent the crud from falling into the gap between piston and bore and then use a scotchpad / non-metallic kitchen scouring pad, perhaps with a little oven cleaner, to clean the crown.
At the end of the day, it doesn't need to be spotless, and, if it has built up an excessive amount of carbon due to poor stem seals, it will soon be burnt off on the first motorway run once the engine is running OK again, so don't risk damaging anything to get the piston crowns clean.
Kevin
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thanks ken will try that although they did feel quite hard to the touch :y
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Got head back and have ordered some bits from Andyc.
Was in my local autofactor to get coppergrease and got copperease (commas brand) and was speaking with him about use of sealant. He said to use sealant with head gasket to get proper seal, but have heard on here only gasket was to be used. Can anyone say which is correct. He also was offering high temperature sealant for this and on the remainder of the work eg manifolds etc. I thought I would ask you guys about that. :-/
Whilst there I asked about the burnt oil on piston crowns and was informed it was use of poor quality oil and not good oil changing. If burning quite bad (toast burnt to cinders) then rings also probably damaged and should also be changed :o. I am now wondering if this is right or is he wanting to sell more stuff?
From what I have seen from my time of ownership I believe previous owner did not service it properly and probably only topped up with cheap oil. :( :(
Thoughts anyone
Thanks in anticipation