View Full Version : Kohler 20 HP Magnum - Wacky Governor?

12-22-2007, 02:08 PM
Got a 20 HP Kohler Magnum that starts fine and runs fine until it warms up. After about 5 minutes or so at full speed, it appears the governor kicks in and throttles it down for a second then back up for a few seconds, then back down, etc... I use if for pushing snow and even at the lower rpms it still seems to have plenty of power at the slower speed.

So far, I have replaced the air and fuel filters... Any advice on what to check next?

Thanks and Happy Holidays,

- John

12-22-2007, 05:33 PM
Sounds like you could have a leaning carb issue, Start the engine and run till it starts acting up. At this point start applying the choke SLOWLY and see if it smooths back out.

If so try opening the low speed adjuster a little, If this doesn't solve the problem the carb may need to come off and be cleaned internally. Spray carb & choke cleaner with the little straw thru ALL ports and passages followed by compressed air if available.

Before removing the carb check the fuel tank cap and make sure it's venting properly.

12-25-2007, 12:26 PM
I don't think it's the governor either, I'd be for cleaning up the linkages real good, compressed air get all the crud out of around the carb, might need a new fuel filter too! On that note replace the air filter also (unless it's been recently done), it sounds more like some kind of air / fuel mixture getting messed up.