Yardman w/22 hp Kohler with Northstar (jk)

[flynlo21]

First of all, YES, I own a Yardman mower. It's 12 years old and save a carb rebuild and two spindles, has been remarkably reliable despite being used as a real tractor on many occasions. It's a 1997 model 834, Hydro stat, 50 inch cut, HD garden tractor.
I bought it because of the 22 horse Kohler command on board (and also because when Monkey Ward was going out of business I got it for 50% off.
Down to business, for the past couple of months, the mighty Kohler has been acting like it has the Northstar system. It runs great for a few minutes, then kicks off one cylinder and runs like crap, emitting lots of raw gas fumes. If I stay with it long enough, it sometimes kicks back in and runs like a champ.
I am not mechanically inclined, but have changed fluids, filters, plugs, dumped the tank, and run numerous cleaners through the carb.
Has anybody experienced something similar with a Kohler? Any suggestions?
...and yes, the hood self destructed and I'm running it naked.

[RWEST]

Possibly the electronic ignition module?? The 25 HP Kohler in my Crafstman tractor did the same thing and a new module fixed it. Maybe...

[Ken]

My Kohler twin started running rough then quit starting all together. replaced the ignition module and corrected this problem but had cleaned the carb. and now had the problem of running like it was full choked. found the check valve was sticking from a gum maybe jelly bean type of gunk in fuel line and around check valve recleaned and engine now again starts easly and runs proper.
Just a suggestion if have a ignition anti diesel valve in bottom of carb.this will cause a problem that seems like a out of time ignition. which back fires and then flywheel key will sheer. just clean the anti diesel valve. A new one is 70 bucks. Voice of experance.
ken

[flynlo21]

Hi guys, just got the Yardman mobile again. In addition to the aforementioned firing issue, I backed into the left front axle and bent the L shaped piece that comes off the crossmember. Tires were point in opposite directions. 32 bucks and we're back in business.
After spending 3 bills at the local "Authorized" Kohler repair center (authorized to rip me off), I'm going to try your ignition module suggestion.
Thank you for the help and I'll let you know what I find out.