Omega Owners Forum
Omega Help Area => Omega General Help => Topic started by: rustym95 on 31 January 2010, 23:07:45
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Think the tappets are lose again or the cams, tap tap tap when cold (loud) then when engine warm'd up its gone, or could it be somthing els??? :-? :-?
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Think the tappets are lose again or the cams, tap tap tap when cold (loud) then when engine warm'd up its gone, or could it be somthing els??? :-? :-?
My 2.2 was the same, noisy on cold start-remedy:
Several short oil changes with VX semi synth 10w40, one with flush, one with valve lifter treatment, one standard.
New manifold gasket and replacement of broken studs, new exhaust, replacement catalytic converter.
Two things were the problem; the lifters were noisy which the oil and treatments helped, and the exhaust was leaking in several places which was worst when cold before it expanded.
Now MUCH quieter :y
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Think the tappets are lose again or the cams, tap tap tap when cold (loud) then when engine warm'd up its gone, or could it be somthing els??? :-? :-?
Cams loose - you'd better hope not!!
As above either sticking cam followers(tappets) - (oil & filter changes to cure) or leaking exhaust manifold. Most likely sticky hydraulic tappets
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My money is on exhaust manifold gaskets. :y
Kevin
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I'd say the same - although I changed some 3.0 cam cover gaskets not long ago, and many of the camshaft bearing shell bolts were visibly half way out :o
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I'd say the same - although I changed some 3.0 cam cover gaskets not long ago, and many of the camshaft bearing shell bolts were visibly half way out :o
Hhmmm! I might just check my bearing shell bolts soonish. A bit of a tappetty noise at startup but otherwise seems to be going fine.
What's the torque on these bolts? is it 8nm as stated in the haynes book of lies?
The above book also says that if the bearing cap breaks (because of an incorrect tightening sequence) then the complete cylinder head assembly must be replaced, because the caps are matched to the head and not available separately!
So I guess the message is, if doing this job be careful and tighten down in a outward spiral gradually - which all of us know don't we?
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Mine's been tapping more on startup this last few weeks, I've had Flu' the last two weeks and hardly started it, plus the very cold weather will have thickened the oil,(changed recently with GM semi 10w/40w). Once its warmed a bit it's ok. I've had this before with hydraulic tappits.
One of the reasons for using quality oil and quality petrol is to help cut down on the gunging up of these parts. Cheap fuel doesn't have the necessary detergents.
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As previously said, worth checking exhaust manifold gasket, or the manifold itself (4 pot ones do crack)
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it sorted now bolts on cams loose again, can you get any of them bolt lock for this engine to stop them coming loose, been out after doing it quied as a mouse now, the bolts seam to come loose. think may help doing it in the cold as last time it was hot, and metal shrinks in the cold. thanks for your help have a nice day. :y
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What's the torque on these bolts? is it 8nm as stated in the haynes book of lies?
Yep. :y
The above book also says that if the bearing cap breaks (because of an incorrect tightening sequence) then the complete cylinder head assembly must be replaced, because the caps are matched to the head and not available separately!
Yes, the caps are line-bored on the head so it is vital that they are not swapped between heads and that they are refitted in their original positions when disturbed.
If one were to break you could probably replace the cap and get the journals line-bored again. Might well be cheaper to change the whole head though.
So I guess the message is, if doing this job be careful and tighten down in a outward spiral gradually - which all of us know don't we?
Yes, and I personally would add a dab of thread locking compound to each bolt. Not sure if this is officially recommended but they are relatively loosely fitted and subject to a lot of vibration.
Kevin
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ill try that then thanks again :y