Kohler SP27 bending push rods

[Grooving]

This engine is on a Toro Z master. It was run for some time with blown exhaust manifold gaskets. Finally it burnt a valve. The valve has been replaced but now it bends the push rod.
My thoughts; wrong valve installed, too long or bad lifter.
Any other ideas are gladly accepted

 

[ILENGINE]

The Command engine has hydraulic lifters and can get over pumped causing the valve to bottom out on the guide causing bent push rods. The guide could also have moved causing the rocker to hit the guide causing a bent push rod. Have seen it several times on briggs, but not on Kohler as of yet.

If Courage engine then I would say that a valve guide has moved toward the rocker causing it to hit the rocker leading to bent push rods.

 

[chance123]

Did "you" replace the valve? Or did you pay a shop to do it.

 

[Grooving]

Seems I miss communicated with you guys. Talked with the client more. Valve was not replaced, push rod was, buy local trusted mechanic. Engine smokes a lot at full throttle and sounds like it is coming apart. This problem may have been around since the mower was new. If they run it at 3/4 throttle the engine runs smooth, no issues.

Valve guide moved? I like that idea
Maybe wrong size push rod? Ever here of that on?
Where might I find a manual on this motor with clearance specs?

Thanks

 

[chance123]

Give me the model and spec numbers and I can tell you. Better yet go to kohlerplus.com This is Kohler's site and it will only run with the internet Explorer browser
(sign in as "guest")

 

[Rivets]

If the mechanic did not take the time to preload the hydraulic lifter and go through Kohler sequence, the push rod will bend. I would also wonder why he did not service the valves when the push rod was replaced. What was the cause which resulted in the original bad push rod?

 

[Rivets]

Here's a site to obtain a service manual.

Free Kohler Service Manual Downloads : Kohler Engines and Kohler Engine Parts Store, Genuine Kohler Engine Parts

 

[Grooving]

Downloaded the manual for CH740. Will look into this issue
Do you guys recommend replacing the valves, guides, seals, and lifters?

thanks

 

[Rivets]

With out knowing what caused the problem, it is tough to say what route to go. I always recommend servicing the valves (cutting the seats and refacing the valves) anytime the head comes off. If there are seals, replace them. Lifters and guides are a question, only replace if I feel they are the cause of the problem. You need to find the cause of the problem, or you may be throwing money away by just replacing parts. Remember each engine we talk about here is different, and we cannot diagnosis through posts with ant certainty.