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Discussion Starter #1
right the cambelt went on the 156 ive got, got the head off, bent valves on pistons 3 and 4 exhaust only. but having a look at the pistons, there has obviously been contact but not damaged them or really even dented them.

this is the problem i have

pistons 1 and 2 are lower in the bore! sounds crazy but they are, if you put piston 1 at tdc the piston is around 1 mm lower then the top of the block and piston 4 is flush, then if you put number 2 at tdc then thats 1 mm lower and number 3 is flush, but the damaged valved were 3 and 4 so you would think that they would be lower!

im assuming this isnt normal, never owning a car like this i cant do a comparrison but this is surely not right!
 

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Yep, get the sump off and pull out the pistons, the shells should be replaced anyway, but a mm down, that leads to bending of the rods. Do all the pistons have the same code on top? e.g. 2E2.
 

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Discussion Starter #5
this is the crazy issue i have the higher sitting pistons ARE the ones that had contact!
but i will be pulling them out next day off
but it makes no sense that
 

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Could be buckled and making them ride higher? Smakey will know.:):
Not sure I see what you're getting at.

A old shell I just measured was approx 1.5mm thick. If yours have spun, then there is your answer. If the shell on the con rod has spun the piston could indeed sit lower at TDC
 
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