Kohler Command wants to quit running stumbling when hot

[racer44]

I have a 19 year old Simplicity riding mower with a Kohler Command 15 hp engine . Has near 700 hours on it, after maybe 1 hour mowing starts stumbling and today cutoff. I came in and had dinner and after cooling started right up and I finished mowing no issue.I have checked [color:#3333FF][/color]the carburetor no trash. This started showing up about a month or so ago.Could it possibly be the ignition module failing or the spark advance module. Something is getting hot and starting to fail. Any ideas what it maybe what I should check don't want to just throw parts at it.
Thanks,

 

[PowerSurge]

I think you're on the right track with the ignition module.

 

[jeepman3071]

Originally Posted by PowerSurge
I think you're on the right track with the ignition module.



+1 on the ignition coil.

 

[Dinoburner]

Yes, check spark first and if good check for vapor lock. If there is a clear plastic fuel filter it will have very little in it when vapor lock occurs.

 

[CatCam2]

I have the 16HP variant CV16 Kohler Command and I get something very similar. When it heats up after 10 min or so I loose power and when it stumbles uder load I get a backfire. I also thought it was the ignition coil and spent $65 on a new one.....no dice. I changed the carb.....no dice.....hydraulic valves so there is no adjustment there.....governor seems to be advancing throttle under load so that's good. New fuel lines, filter, gas cap, spark plug, air breather/filter.....So now I'm thinking possible head gasket.....Mine is 20 years old with 770 hours on it. Does not burn oil or smoke at all.

 

[gman2304]

You might also make sure there's no dirt, dried grass clippings etc blocking the cooling air in and around the engine tins. I blow mine out with either compressed air or a leaf blower several times each Mowing season.

 

[andyd]

First thing I did to the Kohler 491 cc was to strip off all the tinware and remove the mouse nests.

 

[vwmaniaman]

Sounds like vapor lock. Winter or summer gas in there? My Briggs does the same when I try to use my winter generator gas in it.

 

[Touring5]

I had to replace the ignition coil on a CV15 engine last year. Bought it off amazon for around $15, so it's a cheap part to throw at the problem.

 

[mk378]

+1 on the mouse nests. If you haven't yet taken the top cover off to check the cooling passages, that's the first step.

 

[Merek]

We had an early 90's Simplicity Broadmoor with the 14hp Kohler and had to replace the ignition coil. I need to replace the one on my Briggs opposed twin due to hard starts when it's hot and has been running for awhile it is a pain to get running again so I either let it cool down or just leave it running if it's only going to be a few min, common problem on those Briggs as they get heat soak and overtime it causes it to break down. I suspect that Kohler has it's own issues with these as well from the sounds of it.

Video on how to replace it on a Kohler.
https://www.youtube.com/watch?v=kAVubYlhAwM

 

[andyd]

To the OP please post your progress, This generation of Kohler is better than the equivalent B+S and after mkt parts are readily available for it and the Craftsman/Husqavarna/Electrolux/etc mowers. The fuel line between the fuel pump and the carb runs under the tin against the engine. Potential for a mouse house is big. When I got my LT1750 Craftsman home it had a new born mouse crawling out of it.So I knew. Probably saved me from what you're going through.

 

[racer44]

Ok,I removed the fan housing from my 19 year old Kohler CV-15 Command engine. First time I have had to remove it, Glad to say No mouse house! There was some crud buildup inside the fan housing around the starter and maybe 1/3 the way around the housing. Cleaned every thing up rolled the mower outside the garage. Used the air compressor blowed all the dirt and dust and used brake clean and a rag cleaned everything up. The cylinder and head was rather clean. I ordered a Kohler ignition module and replaced the spark plug. Cut the yard today and I am glad to say the engine ran great and the module seams to have corrected my issue of missing after it got good and hot. Thanks all.

 

[CatCam2]

UPDATE: See my post from last year!! Glad I didn't trash it!!

I had similar problems with my 22 year old Kohler Command CV16s engine on my Scotts1642. It was the **** speed advance module (SAM) that connects to the ignition coil. My mower would start but power was lacking and if I hit any heavy grass I would have to choke it immediately and then play with the throttle until it decided to run correctly. After 10 minutes or so it would just kill. SO, Kohler doesn't make this SAM anymore....and the fix is to order part Part# 12 707 01-S DASI. This "conversion" does away with the SAM module..... $135 later my 22-year-old mower is running like a champ.

 

[Dinoburner]

Thanks for the follow up