147 Selespeed/engine failure - Page 2 - Alfa Romeo Forum
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156 selespeed

Originally Posted by Phear View Post
With bent / broken valves I would expect 0 compression. I had the tinyest little chip on a valve and compession was zero, if they are bent or broken it wont even seat properly and will be much much worse. Low compression is probably worn rings or a complete knackered head gasket. Now to have all your piston rings wear identically across the board would be pretty damn unlikely!
You can have bent valves and still show some compression. Valves bend at varying rates. I've built plennty of engines and seen a variety of bent / broken valves as well as some that don't look bent until you try to lap them in - you notice they don't seat all the wat round...
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Originally Posted by stoyce View Post
Quite possible...

Id get the timing checked first and go from there. If thats OK, you could see if any garage out there can perform a cylinder leakage test - that will confirm where the problem is. I don't think too many garages do this though??

Personally, I think you'll find the answer in the timing belt area...
Yes, if the belt has jumped you could have both valves closed much later in the compression stroke, which will reduce the compression test result. It would also explain how all cylinders have an equally low result.
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I agree with David C and Stoyce. I'd get them to make sure that the belt and tensioners are correct and that the timing is set right before you take the head off. You can't really lose much and my well save a packet.
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Last edited by AlfaNoMore; 09-03-10 at 18:58.
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147 , failure , selespeed or engine

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