It depends upon how much of the valve stem is exposed beyond its guide, how far the valve opens into the combustion chamber and the point at which the valve/piston collision takes place. Our valve guides protrude quite a long way into the inlet port. Many don't. The further open the valve is (more of the stem unsupported) when it happens the more the bending, as e.g. when a cambelt breaks. A vertical valve with little normal running clearance 'twixt piston crown and valve head will be more likely to bend the stem whereas an angled valve like ours with a more generous running clearance will most likely do most damage to the valve head (because it is at an angle when the piston hits it). If a valve spring or collets fail and the valve drops into the cylinder..................... But I guess you were aware of that already .Expat wrote:SPRIDS, re your pic. How does a valve get bent in that area? Would be in the guide surely
valve hitting piston
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Re: valve hitting piston
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'There is a tide in the affairs of men
Which taken at the flood............'
Which taken at the flood............'
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Re: valve hitting piston
Well if I wasn't then.....I am now!
Have never seen such carnage, and don't really want to. Not on any of my babes anyway.
Have never seen such carnage, and don't really want to. Not on any of my babes anyway.
Keep shiny side up.
These are my principles, if you don’t like them, I have others. (Groucho Marx)
These are my principles, if you don’t like them, I have others. (Groucho Marx)