Omega Owners Forum
Omega Help Area => Omega General Help => Topic started by: The Cambelt Kid on 08 October 2007, 21:29:24
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Hi Guys,
I've just changed the cambelt on my 2.6 and when i first cranked it over aftger the change it made a ticking noise, not too loud but certainly not good at all. I installed a genuine kit and followed all the instructions in the DVD. I took the time to make sure the timing was spot on, i think i ended up manually cranking it over 15+ times in the end...
Now when i first put the belt on and then cranked it over i forgot (like a total fliocking idiot) to tension the belt, which caused cam 1 to slip 4 teeth. :-[ (gulp). Now being a clever dick i manually moved the cam back the the original position. So all in all the crank was TDC, cams 1+2 was nob on and 3+4 was ever so slightly to the right hand side on the cam marking on the cam timing tool, the timing mark was still inside the cam marking though. Maybe i#m just being a bit fussy, but i really wanted the timing to be spot on. Anyhow i cranked it over by hand quite a few times and didn't feel any more pressure than i usually would.
My question is... What damage can be caused if the cam slipped as it did? I never ran the car with the timing out, so i'm hoping that i've not caused any damage...
I'm on the verge of being out of my depth now so i might even start begging for a visit :-[
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In fact i really feely like :'( I've really mucked up this time!
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I guess the only way to tell is compression test. Hopefully you've got away with it.
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I guess the only way to tell is compression test. Hopefully you've got away with it.
Can it really be that bad? It's not like i drove at 50mph and then it went bang, at most it was ticking over.
I think my dad has a compression tester. So i guess i will have to manually crank it over and compare each pot?
It ran ok on tickover and didn't cough of splutter, just the usual hum with a ticking noise.
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Are you sure the ticking was not there before, ie- injector tick..
Have you tried pulling the camcover whilst its running to see if the tick gets worse or better??
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Pulling the cam cover? The noise sounds like it's not timed correclty, even though i spent an age getting it tip top!
If all the cams are on the timing mark and the crank is TDC on the water pump, surely this it how it should be.
Is it possible to damage the valves by one cam slipping when manually cranking over?
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Only if you force it, otherwise most unlikely.
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Well i guess i could have done then. I was cranking against the compression of the engine and putting in a few grunts so i think it's possible... :'(
Come to think of it, it would take a breaker bar and one hell of a push to force a valve into a pot... wouldnt it?
What's the score it i've f***ed it?
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Well i guess i could have done then. I was cranking against the compression of the engine and putting in a few grunts so i think it's possible... :'(
Come to think of it, it would take a breaker bar and one hell of a push to force a valve into a pot... wouldnt it?
What's the score it i've f***ed it?
New valves if the guide's are OK...
but look on the bright side.
If I were you, I would get that cambelt cover off, and be double checking EVERYTHING... sometimes you can get strange noises if the water pump pulley etc doesn't sit right - we had this on Hotel21's car a few weeks ago
Once cam timing again confirmed as spot on - and it's been cranked by hand, see how it runs. You may have got away with it.
At this point, once confident timing is fine, I would be compression tested.
If compressions are OK, power seems ok, see if your noise settles down. Might just be a dry follower.
Can you confirm - did you RUN the engine with the tensioner backed off? (I really hope not!)
If you need a visit - then you can consider me as an option, but I DO have some time constraints and other pressures at the moment, so I don't have a hugely open diary...
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Well i guess i could have done then. I was cranking against the compression of the engine and putting in a few grunts so i think it's possible... :'(
Come to think of it, it would take a breaker bar and one hell of a push to force a valve into a pot... wouldnt it?
What's the score it i've f***ed it?
New valves if the guide's are OK...
but look on the bright side.
If I were you, I would get that cambelt cover off, and be double checking EVERYTHING... sometimes you can get strange noises if the water pump pulley etc doesn't sit right - we had this on Hotel21's car a few weeks ago
Once cam timing again confirmed as spot on - and it's been cranked by hand, see how it runs. You may have got away with it.
At this point, once confident timing is fine, I would be compression tested.
If compressions are OK, power seems ok, see if your noise settles down. Might just be a dry follower.
Can you confirm - did you RUN the engine with the tensioner backed off? (I really hope not!)
If you need a visit - then you can consider me as an option, but I DO have some time constraints and other pressures at the moment, so I don't have a hugely open diary...
The only time i ran the engine was after the timing was spot on and all bolts were torqued up. I didn't want to run it while the plenum was off so when it was started the car was back in one piece.
I'm interested in how Hotels water pump sounded, was it that bad you thought it was the timing?
As i say it was timed up and tourqued up before running.
:-[
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Well i guess i could have done then. I was cranking against the compression of the engine and putting in a few grunts so i think it's possible... :'(
Come to think of it, it would take a breaker bar and one hell of a push to force a valve into a pot... wouldnt it?
What's the score it i've f***ed it?
New valves if the guide's are OK...
but look on the bright side.
If I were you, I would get that cambelt cover off, and be double checking EVERYTHING... sometimes you can get strange noises if the water pump pulley etc doesn't sit right - we had this on Hotel21's car a few weeks ago
Once cam timing again confirmed as spot on - and it's been cranked by hand, see how it runs. You may have got away with it.
At this point, once confident timing is fine, I would be compression tested.
If compressions are OK, power seems ok, see if your noise settles down. Might just be a dry follower.
Can you confirm - did you RUN the engine with the tensioner backed off? (I really hope not!)
If you need a visit - then you can consider me as an option, but I DO have some time constraints and other pressures at the moment, so I don't have a hugely open diary...
The only time i ran the engine was after the timing was spot on and all bolts were torqued up. I didn't want to run it while the plenum was off so when it was started the car was back in one piece.
I'm interested in how Hotels water pump sounded, was it that bad you thought it was the timing?
As i say it was timed up and tourqued up before running.
:-[
Timed up... torqued.. and tensioned? I that case, if you didn't force it by hand either, I think you should be alright...
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Thanks for the offer James, where are you based?
I will triple check all items before calling in the A-Team, so as to waste your time.
Cheers
Marc
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Still not clear if you ran the engine with the tensioner not set right.
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Still not clear if you ran the engine with the tensioner not set right.
Tentioner was adjusted and torqued before i even put the key in the ignition.
Just to re-clarify, from my understanding, would you agree that it'd take a breaker bar on the crank to bend a valve?
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Still not clear if you ran the engine with the tensioner not set right.
Tentioner was adjusted and torqued before i even put the key in the ignition.
Just to re-clarify, from my understanding, would you agree that it'd take a breaker bar on the crank to bend a valve?
I think you'd be unlucky to damage, but compression test will confirm.
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Well TB i can only hope as i can imagine bent valves can cost, not to mention the work involved :'(
I'm just thinking if any other part i came into contact with could cause a knocking niose such as this?
When the car did tick over it sounded fine and didn't sound like it was suffering from low compression. I take it that if one has low compression the car was idle rough.
Thanks for your help guys, you've really perked me up. I was about to cry with shame, but now i am working on a plan of attack.
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Well TB i can only hope as i can imagine bent valves can cost, not to mention the work involved :'(
I'm just thinking if any other part i came into contact with could cause a knocking niose such as this?
When the car did tick over it sounded fine and didn't sound like it was suffering from low compression. I take it that if one has low compression the car was idle rough.
Thanks for your help guys, you've really perked me up. I was about to cry with shame, but now i am working on a plan of attack.
I suspect the noises are not damage, but something else. Valves could bend or just get the edge chipped bent, hence reducing compression so it will still run, but noisy. Thats worse case. Hopefully, the noise is something simpler
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Well TB i can only hope as i can imagine bent valves can cost, not to mention the work involved :'(
I'm just thinking if any other part i came into contact with could cause a knocking niose such as this?
When the car did tick over it sounded fine and didn't sound like it was suffering from low compression. I take it that if one has low compression the car was idle rough.
Thanks for your help guys, you've really perked me up. I was about to cry with shame, but now i am working on a plan of attack.
I suspect the noises are not damage, but something else. Valves could bend or just get the edge chipped bent, hence reducing compression so it will still run, but noisy. Thats worse case. Hopefully, the noise is something simpler
Hmmm chip bent! I didn't think of that one.
This is doing my head in, i'm thinking of all the bad and expensive things that can go wrong...
If lets say it's worst case, how difficult is a head removal and valve replacement? not to mention cost?
Cheers
M
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How far did the timing go out when you cranked it by hand? (just re-read. 4 teeth. Enough to cause damage if running but probably not by hand)
I'd say the most likely explanation is that the timing slipped, maybe you got valve to piston contact but it could well be that it just forced some oil out of a hydraulic follower and it's going to be noisy for a few minutes before it fills up.
If it was cranked over by hand a lot before starting it could be that this has just emptied the followers a little.
If you're not positive the timing was right when you put it together take the cam cover off again and double check. Make sure the idlers are torqued correctly, the timing is still OK and the tensioner marks are set correctly for a new belt. Make sure you're using the correctly numbered timing marks for cams 1,2,3 & 4. The latter two are close together on the sprockets and easy to misread. Ensure the tensioner nut is torqued then put it back together and start it again.
On a 2.6 the idler that feeds cams 3 and 4 is not adjustable so the cam timing on these can only be changed in 1 tooth increments. Sounds like it's close enough.
This time, give it a few minutes to warm up and hold it at maybe 2000 rpm for a minute or so assuming it sounds safe to run. Once the lifters have filled up it should quieten.
If not, a compression test should tell if there's any damage done.
Fingers crossed for you :(
Kevin
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Well TB i can only hope as i can imagine bent valves can cost, not to mention the work involved :'(
I'm just thinking if any other part i came into contact with could cause a knocking niose such as this?
When the car did tick over it sounded fine and didn't sound like it was suffering from low compression. I take it that if one has low compression the car was idle rough.
Thanks for your help guys, you've really perked me up. I was about to cry with shame, but now i am working on a plan of attack.
I suspect the noises are not damage, but something else. Valves could bend or just get the edge chipped bent, hence reducing compression so it will still run, but noisy. Thats worse case. Hopefully, the noise is something simpler
Hmmm chip bent! I didn't think of that one.
This is doing my head in, i'm thinking of all the bad and expensive things that can go wrong...
If lets say it's worst case, how difficult is a head removal and valve replacement? not to mention cost?
Cheers
M
Doable, and I have all the kit to do it.
If you're in the sh*te, we'll get you out of it somehow.
I should still also have lots of spare V6 Valves (inc sodium filled exhaust ones fitted to 3.0l) which would be better on LPG (I'd have to confirm they would fit, but don't see why not).
I still think though, that there is a slim to none chance of damage, and this won't have to happen.
I bet you've done something really silly - like not tighten a pulley.
Check the oil level etc.. it may not definately be related..
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Still not clear if you ran the engine with the tensioner not set right.
Tentioner was adjusted and torqued before i even put the key in the ignition.
Just to re-clarify, from my understanding, would you agree that it'd take a breaker bar on the crank to bend a valve?
Would take very little to bend a valve, the valves move at 45 degrees to the bore so if contact is made between valve and piston then it is easy to bend the relatively thin valve stem. You only need the valve head to be 0.006" off the seat to spoil engine performance and economy as I found out recently.
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I think I would re-check the tensioner adjustment, if it is set too low then it can return to its end-stop as the engine rotates which produces a ticking noise in-time with the engine.
If the noise is more from the top of the engine then I would suspect a noisy injector or a cam follower that has not fully filled with oil yet.
If the tensioner checks out OK then run it to check performance and economy, nois might disapear with use if it is a follower, if it is using more fuel or seems 'flat' then you should measure cylinder compressions and manifold vacuum and post the results.
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Nice one chaps, you are pulling me back from the depths of depression here.. :)
When manually cranking over i didn't feel any metal to metal resistance, i only felt compression. So for the moment i am pinning my hopes on the 'empty lifters' theory, which i did think of first but given the work i had just done on the cambelt i never gave it a second thought. Thinking about it i did manually crank it over 15+ times as i was being a bit an*l about the timing, so if this would empty the lifters of oil then i do stand a chance.
Having said that TB scared me into thinking that 0.006 of and inch can be a ball ache, so this is on the cards too. My dad has replaced his head on two of his Volvos (twin cam and single) before so removing the head and replacing valves isn't out of my dad's depth, but it certainly is mine. I am sure if there is any damage it will be contained to the drivers side head as the passenger was always correct. I understand that the drivers side head is easier to remove due to the available access.
James - Thanks for the offer of the valves, i understand that they can be costly so if i need them i hope to god the 3.0 ones will fit. I will sort you out some $$ if it comes to that. Is it common for all 12 valves in one head to be bent?
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Needless to say i didn't sleep much last night, so all you guys are a ray of bright light to me! :y
I can LPG a car, change a belt on a 4pot and even change a wheel, but i don't think i can change a V6 timing belt very well :-[
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Heres my two peneth....
1) Your followers were slightly noisey when I saw your car teh other day....only slightly.
2) I doubt you have done any valve damage.
3) Let it run for 10-15 minutes and see if it quietens down, I suspect it will because when you turn it over like you did, you can pump some oil out of the followers and they can be noisey for quite a few minutes afterwards and given that yours were very slightly noisey anyway....I feel you have nothing to loose and I suspect its this that you can hear.
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Heres my two peneth....
1) Your followers were slightly noisey when I saw your car teh other day....only slightly.
2) I doubt you have done any valve damage.
3) Let it run for 10-15 minutes and see if it quietens down, I suspect it will because when you turn it over like you did, you can pump some oil out of the followers and they can be noisey for quite a few minutes afterwards and given that yours were very slightly noisey anyway....I feel you have nothing to loose and I suspect its this that you can hear.
I will try that this evening when i return from work and post the results.
Cheers
Marc
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If it's any consolation, I lost control of cams 1& 2 when trying to correct the timing during the belt change on my 2.6. After reassembly it most the most awful rattle at first, then went quiet, must have emptied the lifters.
It's worrying for a while, but does not seem to have left a problem, hope yours is similar.
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If it's any consolation, I lost control of cams 1& 2 when trying to correct the timing during the belt change on my 2.6. After reassembly it most the most awful rattle at first, then went quiet, must have emptied the lifters.
It's worrying for a while, but does not seem to have left a problem, hope yours is similar.
Hi Mike,
I hope so too! I take it that you manually cranked it over a few times just like i did?
I found it difficult to bring in cams 1+2 so i could lock it because all 4 cams were 1 tooth retarded. The only adjuster my 2.6 had wasn't making a blind bit of difference...
I'll report back after 7 tonght...
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Hi Chaps,
Now this post has been demoted to the second page I thought I’d bring it back to the top...
Since my terrible sleepless night and a day at work not doing any other than worrying about my baby, I arrived home tonight armed with a few ideas as to what was causing my car to rattle like a fraud fiesta.
Some of you mentioned that the noise could have been caused me cranking over the engine by hand far too many times and thus drawing oil out of the lifters. So the first thing I did when I got home today was start her up and left her on tick over for a few mins, and within the first minute the noises began fade away! So with the engine still running I topped up the coolant and gave her a few very light blips, working my way up to 2k rpm. After a few mins at 2k the noise completely disappeared! Now as you can imagine the smile on my face stretched from Derby to Nottm
I then took her out for a run on the A52 and noticed that it seemed ever so slightly smoother and more responsive. Also didn't notice any signs of performance loss or any odd noises, which put a little confidence into the work I’d carried out.
So all in all this was a happy ending and I owe all you very kind chaps a very big thank you for all the help and support you have shown. I was really at the bottom of a hole and you’ve all contributed to pulling me out! And to think the last thing I would have done is run the car for a few mins, whereas without OOF I would have stripped the front end and maybe even ripped a head off...
Thanking you
Marc
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Nice one :y I was just about to have first digs on parts off your car as well ;D
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Well done :y
Glad it's OK. Big sigh of relief!
Kevin
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Good job....see, you can change a cam belt!
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Some of you mentioned that the noise could have been caused me cranking over the engine by hand far too many times and thus drawing oil out of the lifters.
Just to pick on something you said here, I wouldn't discourage anyone from turning the engine over by hand as much as is required to satisfy themselves that everything is timed up OK. Better to do this than to start it with incorrect timing.
The issue with the lifters is that, when the engine stops normally, maybe only 1 or 2 pairs of followers are under compression against the valve springs. They probably lose a little oil and rattle for a second or two at start-up as they refill. When you turn the engine by hand, each follower gets a fair amount of time under compression so all 24 will have "leaked down" a little. This makes a much more formidable racket at start-up and it takes a little longer of the whole lot to refill.
As long as the engine isn't revved hard before the lifters refill it does no harm.
Kevin
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You can breathe again now :)
Glad it wasnt anything more serious, its amazing how paranoid we get about noises when we have had something in bits.
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Boy am i a happy chappy! ;D
Mark - Does this mean i can joint the V6 hall of fame? 8-) Even if i did poop my pants while doing the belt...
Also i think i've found a lead for your LPG kit, Jia @ Micromise called yesterday and said it may be made/installed by http://www.nicholsonmclaren.com he said you'd be lucky to get a cable for it, but at least its a start!
Cheers
M
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Thats fabulous news Marc :y
You're now the cambelt kid ;D
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Thats fabulous news Marc :y
You're now the cambelt kid ;D
Things like this make me realise exactly how precise and complex the modern combustion engine is, even more so for the V6. I recall my dad replacing and skimming his Volvo head a few years and to think that was a single cam 8 valve 2.4, not the 24 valve monsters most of us drive. To think 6 thou of an inch would cause running issues is crazy!
Anyway thanks once again chaps, i’m the happiest man on OOF right now!
Cheers
The cambelt kid!
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Like the name change. Sounds like you've earned it. :y
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Things like this make me realise exactly how precise and complex the modern combustion engine is
You need to watch this. Shame it's only a 4 pot though.
http://www.spikedhumor.com/articles/128561/3D_Engine_Assembly_and_Operation.html
Let me know at what time you correctly identify the type of engine ;). I thought I had it 30 seconds in but then the timing chain appeared and my choice had a belt :-/ Finally got it at about a minute.
Kevin