Can't get the governor to set ? Simplicity Cobalt Zero Turn

[Tiger Small Engine]

I have seen several Kohler Governors that have broken the internal (plastic) gear. If this has happened to yours, you have a big job ahead of you. If you have limited experience you may find it easier to look for a used engine or even an old tractor that has a good engine. Generally you can "probably" use any engine of similar hp as long as it has the same size crankshaft. Now as far as the governor goes, lots of people play with it to solve problems that actually have NOTHING to do with the governor, surging for instance. Except for a broken or stretched spring there is literally NEVER a legitimate reason to mess with it. I recently worked on a Kohler V-twin where the original owner took apart the throttle/ governor linkage and the installed the bracket upside down, putting it back together properly was a horror show. If you do not have lots of experience with the exact engine model you are working on, use your cell phoneAand take lots of pictures to be certain you are putting it back together properly. Again I stress that there is a 99.5% percent chance that there is never a reason to mess with your governor something else, probably the carb that is causing the problem.

Yes, most of the time it is NOT the governor, it is usually the carburetor. Homeowners start watching YouTube videos and think they need to reset the governor.

As far as compression test goes, you want no more than a 10% differential between cylinders on compression test. So 140 psi on higher cylinder would mean lower cylinder should test out no lower than 126 psi. So compression now comes into play.

 

[Chipg1956]

Most small engines (if not all) have compression releases which will give a false impression of the condition of the engine. Instead do a leak down test. Leak down gauges can easily be made or bought fairly cheaply but a gauge really is not necessary. To do a leak down test figure out a way to hold the crankshaft when at TDC with both valves closed. pressurize the cyc with air through the spark plug hole look, listen for leaks. If you are unable or do not wish to hold the crank, simply remove the rocker arms off the valves.

 

[Chipg1956]

By the way, when you state the the governor will not set what do you mean? The engine over revs? If you are doing a compression test what is the additional problem you are trying to solve?

 

[Chipg1956]

Did a compression check this morning , , not a good out come , , , facing the engine -- left cylinder is 100 psi - - - right cylinder is 140 psi - - - so will this unbalance from side to side effect the way the governor operates ? this engine has 332 hours on it.. thanks

No

 

[Ray G]

If in fact you have set the governor correctly for your engine, and when you hold the throttle linkage, and it is not fighting back, it is possible that the governor gear is internally damaged. Which of course requires removing the engine, opening up the engine, and removing and replacing the governor assembly.

Or is the spring missing?

 

[VegetiveSteam]

That is exactly what I was hoping it wasn't . Now There is no label or decal on this engine, to be certain which it is? From pictures I see on the net it resembles a cv series? Like a 23 25 27 .... Million dollar question - do the cv series use the same governor ?? Or how do I determine what series I have ? Thanks

All the Command twins from 18 to 28 HP use the same governor gear which is part number 24 043 12-S.

And to expand a bit on what chipg posted. For engines with a compression release, the leak down test is really the best test and many engines do use a compression release. For your engine a compression test will be good because Kohler twin cylinder engines don't use compression releases except in a couple of oddball specs. For the best compression test, make sure the throttle and choke are wide open so you get enough air drawn in to get an accurate test. If the throttle plate and choke plate are closed you may get a false low compression reading.

That being said, when I find 150 psi or higher on a Kohler twin I'm done worrying about a compression issue and I move on. When I find low compression via a compression test on a Kohler twin cylinder, I'm going to a leak down test anyway to find where air leaks so as long as you know how to use a leak down tester, and not everyone does, it's the best test.

 

[Forest#2]

I'm wondering what you did to start this engine having issues in the first place? (or had someone else been monkeying around with the engine)

Have you ever seen it operate correctly? (or is it a new to you engine and you are trying to repair it for someone else)

Make sure the govenor spring is connected properly.
Also make sure that the governor arm clamp nut is tightened securely, not just limp wristed. If the clamp nut is not secured good the arm will spin on the shaft when the engine is first started and the engine will go wide open and remain so.
If it still runs wide open when started up after checking the governor spring and doing the proper static gov adjust with the clamp nut secured, trying setting the governor backwards. (backwards means instead of adjusting the governor arm's SHAFT and arm in same direction as the carb throttle opening, go in the opposite direction with the shaft) If the engine then starts and just idles the governor is operating internally inside the engine and you should be able to push on the governor arm and speed up the engine and feel the governor arm pushing against you trying to speed up the engine with the governor) If you push on the arm and the engine picks up speed and does not return to same idle rpms when the arm is released the arm is slipping on the governor shaft.
If setting the governor backwards gets a idle you then know you ARE NOT setting the STATIC governor adjustment properly

 

[rjh1]

Engine is fixed , the governor was in pieces internally.