View Full Version : Kohler ch25 governor problem

01-17-2007, 12:12 AM
My son has a Toro zero turn with a Kohler CH25 twin. Starting late this summer, it was slow to return to idle. Now it revs up too fast and is slow to return to idle.

We suspect that the carb linkage is not moving easy enough. Everything seems to be free and easy to move until you get to the carb. Should the valve which is moving in the carb be fairly easy to move?

Any other suggestions of what could be causing this?

Thank you.

01-17-2007, 12:31 AM
Yes the valve should move freely with and the spring on it should return it idle very easly. Post spec # so I can see your engine and carb. Also check for wear in the carb and the bolts on the butter fly plate, should be two holding it to the shaft have seen them come loose or off causing the butter fly to move around and get stuck on the side of the carb, not a good thing.

01-17-2007, 02:16 AM
We had a Kohler over revving and of all things it turned out to be a small stick that got cought in the linkage. Yours sounds like it needs some WD-40 on the linkage or something. Gas deposits can build up in the carb and cause the shaft to stick as well.

01-17-2007, 07:17 AM
mine does it too

01-17-2007, 07:42 AM
The engine is a ch25S, Spec 68576, Ser 2803318011.

Thanks for the replies. I was afraid that the gonernor internals were gone and that would involve tearing down the engine. We did clean out a lot of junk from around the carb. The engine sits on the ground in back of the operator - almost impossible to keep clean!

Thanks for all the replies.

01-17-2007, 01:33 PM
An initial governor adjustment never hurts either, just make sure you don't pinch the two "ears" together on the governor shaft, as the governor arm will not grip properly then.

02-01-2007, 05:47 PM
Your engine has a carburetor with a mechanical accelerator pump on it. Once in a great while the accelerator pump shaft will become gummy and sticky and cause the throttle to be slow to come back down to an idle. As long as the shaft isn't bent you should be able to clean it up and have it work fine again. If you coat the shaft with a very thin layer of anti-seize after you clean it you shouldn't have the problem again.