Bent push rod/ another loose

Spikeit

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My cousin has a Kohler twin cylinder CH22S that started running badly. A compression test showed 180psi in one cylinder, 30psi the other. Thinking a blown a head gasket, he pulled the 30psi valve cover and found a bent exh push rod and the intake push rod laying loose. Together he and I can't figure why. One would think the exh valve hit the piston (bent push rod) but there are NO MARKS/DAMAGE whatsoever to neither the valve or piston. On to the intake; the rocker arm bolt was good/tight so what would cause that push rod to just "fall out" of place? The lifter has a bad check valve? I'm thinking it collapsed even if just for a second or so. Seems odd to have TWO push rod issues on the same small engine, but on the same cylinder! Until this the motor ran great, started easily, no smoke, no knocking, no noises at all then out of nowhere this. Other then the valve/piston hitting, I can't see what else could/would bend the push rod. I've worked on small engines on-off for many yrs so the repairs are no problem but have no ideas of what the heck happened. :confused2:
 

bertsmobile1

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Usual cause is overheated head allowing the valve guide to shift down then the valve spring becomes coil bound
 

Spikeit

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Usual cause is overheated head allowing the valve guide to shift down then the valve spring becomes coil bound

Your saying the guide moves up in the head TOWARDS the stem end which in turn stops the spring from compressing? My cousin said after I left he took the two valves out/lapped them but didn't mention a guide being out of place and was able to compress the springs. Not saying your wrong and what you said makes sense. I'm just adding what he did later as a follow up. Secondly, what would have caused the other push rod to become loose and fall out of place? Short of a cam lobe being worn down, I suspected a collapsed lifter because the rocker arm bolt was tight.
 
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