High Quality Chainsaw Bars Husqvarna Toys Hockfire Saws

kohler command issue

mowerguy88

OPE Member
Local time
10:22 PM
User ID
34311
Joined
Sep 18, 2025
Messages
10
Reaction score
3
Location
iowa
Country flag
ive got a zero turn with a kohler command ch23s 76586. it ran great all summer. this fall after i mowed for the last time it sat for about 2 weeks and i went to start it so i could service it and get it all ready for next season before i put it away for the winter. well i started it up and it didnt seem to run quite rite so i held my digital tach to both wires and they were both giving me an rpm reading so i know both coils are sending spark. i then misted the muffler right where it comes out of the heads and discovered it wasnt running on the right cylinder. pulled the spark plugs and they were both fouled pretty good so i replaced them and retested. same thing only running on one cylinder. i did a compression test and both cylinders have exactly 190 psi i put a spark checker on the bad cylinder and it has a strong blues spark and it will jump a 6mm gap no problem. i used my inductance spark checker on it and its giving me a high voltage alert on both cylinders which is strange to me. it has vaccum in the crank case while running i havent done a leak down test yet as i have to pull the engine to be able to remove the shroud. does anyone have any thoughts on what it could be before i yank the engine? i dont think its blown head gaskets due to the compression readings. oh ive also removed both valve covers and the valves are operating like they should be on both sides. im thinking its either a bad ignition coil or a compression issue since its so high. i thought these had an auto compression release mechanism if so it must not be working since its got that amount of compression with just the started cranking it. let me know your thoughts please
 

mowerguy88

OPE Member
Local time
10:22 PM
User ID
34311
Joined
Sep 18, 2025
Messages
10
Reaction score
3
Location
iowa
Country flag
also this unit does NOT have the little black box that electronically controls the advance timing for spark.
 

EFSM

Pinnacle OPE Member
Local time
10:22 PM
User ID
29079
Joined
Apr 30, 2024
Messages
971
Reaction score
2,302
Location
Extreme southern IL
Country flag
The CH23 wasn’t as problematic with the head gaskets as the 25 and 27 hp, but the fouling would concern me. How recently had you changed the plugs?
I don’t believe those engines have ACR. I could be wrong on that though.
Is this a single or twin barrel carburetor? I would guess a single barrel, which means that a carburetor issue is less likely to affect only one side. I have seen an intake manifold gasket blow and create weird issues, but having this issue after sitting for a bit sounds more like an electrical issue.
For a leak down test: could you not hold the PTO end of the crankshaft?
 

mowerguy88

OPE Member
Local time
10:22 PM
User ID
34311
Joined
Sep 18, 2025
Messages
10
Reaction score
3
Location
iowa
Country flag
It’s a single barrel carb. I thought if Intake leak but it runs too good to be that in my opinion. I would think even with and intake leak it would still fire on that cylinder. Just might not run great. I could remove the pto clutch and try to anchor it there. I don’t think that’s going to yield me any results tho. High comp reading and no tell tale signs of blown head gaskets. I haven’t changed the plugs since last fall. I mow 4-5 acres a week with it. They weren’t that bad really but it was time. I also thought maybe a diode in the kill wire if this model has that but I would think if that were causing issue it wouldn’t spark at all. I’m going to try and get my inspection camera in there tomorrow and see if I can’t disconnect the kill wire on the coil and see if that yields any results. If not I think I’ll pull it and put coils on it. It has to be a spark/ electrical issue. I’ve been racking my brain on this one.
 
Top