Bolens QT16..and yet another problem..stuck valve

[docrocky]

A friend was in process of investigating why the tractor's idle and engine speed seemed not right. It starts and runs but when the rototiller in engaged and cultivating at a shallow depth (new grass ) had a difficult ..could hardly move forward. So ultimately found that one of the cylinders has no compression. We assume it is a stuck valve. Is there an easy way to unstick it. I have tried Kroil rust buster several injections over several days but no success. any other suggestions other that removing the valve cover?//

From my previous 2 Threads..no one wants to reply...alot of views but no takers. Is the Bolens with the Onan 16 a bad actor?

Thank You

 

[eddie48]

A friend was in process of investigating why the tractor's idle and engine speed seemed not right. It starts and runs but when the rototiller in engaged and cultivating at a shallow depth (new grass ) had a difficult ..could hardly move forward. So ultimately found that one of the cylinders has no compression. We assume it is a stuck valve. Is there an easy way to unstick it. I have tried Kroil rust buster several injections over several days but no success. any other suggestions other that removing the valve cover?//

From my previous 2 Threads..no one wants to reply...alot of views but no takers. Is the Bolens with the Onan 16 a bad actor?

Thank You

Both the Bolens tractor and the Onan engine are good, rugged things to have. Did you check compression both dry and wet? If so, I'd start taking things apart until you get to the problem.

 

[CalG]

It's a flat head engine

Look down the spark plug hole and see which valve is stuck up. Spray it with Kroil if you want, or try to get a bent piece of stiff wire in to push the valve down.

Sometimes access via the exhaust or intake port is possible . You may as well accept that some amount of wrenching will be needed.

 

[eddie48]

My experience is that just pushing the valve back down (if that is what is wrong - could be many things) might work but, likely, will only work for a short time. Pretty soon you will be back to the same problem. Best thing is to get into it enough (take the head off, maybe?) so you can see the problem and really fix it. A little more work now, but less in the long run.

 

[docrocky]

Well I finally followed advice provided and took the head off. One valve was open the other shut. I tried to manipulate the open valve (tried to push it down lightly but not movement. I then cranked it over and the valves both opened and closed as I supposed they were supposed to. But...the piston did not move at all. With very minimal pressure I could push it down and there it remained even when I re cranked the engine. the cylinder wall is not scored. I am rather surprised that the engine starts and runs reasonably smoothly with one side ?broken? Next question is does the Onan 16 have an oil pan on the bottom to easily remove and inspect the push rod and the rest?

Are onans easily repaired or should I be looking for a replacement?

Thank You ..again..and again...and....