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Q: Push rod keeps bending.

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I am having problems with the push rods bending or breaking on one of my cylinders. I bought a new push rod and installed it. The new one bent almost immediately. I need some help figuring out what is causing this problem and how to fix it.

A: A common issue would be a sticking hydrauli...

A common issue would be a sticking hydraulic lifter which can end up with enough of a gap between the top of the lifter and the push rod that the push rod can get sideways and end up bent. Another issue could be a valve sticking closed either from sinking into the seat causing excessive stress on the pushrod or not enough valve stem to guide clearance cause by dirt/sludge in the guide or a bent valve stem causing the valve to bind up in the valve guide. Lifter preload needs to be checked and compared to manufacturer specifications. The lifters can be removed and checked for consistent compression and springback. The head may need to be removed and disassembled to inspect the valves, seats, and guides. You may need to enlist the help of a mechanic and/or machine shop to diagnose the issue.

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