Kubota ZG23 w/Kohler CH23S no spark

[TruChaos]

I have a Kohler CH23S which has no spark. It started getting increasingly difficult to start (lots of cranking) each time I used it.

Now it won’t start. It has spark for about 1- 1.5 seconds then the spark stops. This occurs on both spark plugs. It will start to fire over with only one spark plug but when the spark disappears it dies.

Things I’ve done. Replaced the battery (wouldn’t hold a charge). Cleaned the terminal connectors. Cleaned the key switch and it’s terminals. I tested the key switch with a meter and it’s working fine. Swapped out each relay with a known good relay and there was no change. Inspected the wiring for shorts and everything looked good. Unplugged the delay timer and cleaned the contacts.

It does not appear to have an ignition module. Could the delay timer be bad?

 

[banjodunn]

G'day take the blower housing off so you can see the coils, there will be a single wire with a terminal connected to the coils take this off and check for spark, if still no spark the the coils are bad

 

[tomplum]

There are a few different Kohler ignition systems. The spec number may help. If it does have a single wire to the coil from the harness, you could do as above or unsnap the 6 pin harness and crank it to check for spark. It shouldn't start with the harness unplugged.

 

[TruChaos]

Removing the blower housing is a problem for the ZG23, it's mounted against a bulkhead and to take the cover off would require removing the engine from the mower.

I'll see if I can find the 6 pin harness you mentioned.

 

[TruChaos]

There are a few different Kohler ignition systems. The spec number may help. If it does have a single wire to the coil from the harness, you could do as above or unsnap the 6 pin harness and crank it to check for spark. It shouldn't start with the harness unplugged.

Family: 4KHXS.7252GC
Displacement: 674
Model: CH23S
SPEC No.: 76582
Serial No.: 3402003861

 

[tomplum]

https://www.jackssmallengines.com/jacks-parts-lookup/manufacturer/kohler/command-pro-twin-ch-cv17-25-ch-cv620-750/ch23/ch23-76582-kubota-23-hp-17-2-kw/ignition-electrical-5-24-713-ch18-750

This shows yours as standard ignition. You had asked about the delay module earlier. I work on so few Kubotas that I haven't ran into it, but Deere has Time Delay modules on some of their equipment which will keep them from firing. I do replace those from time to time. Unhooking the engine harness should bypass that.

 

[tomplum]

BTW, I wanted to point out that it is very rare to lose both coils at once. If you come to that conclusion that they are bad, look for power hitting that kill wire. My guess is that when you pull the connector that you will have spark. But that's from here...

 

[TruChaos]

I found and corrected the problem. Before I resolved the problem, I disconnected and cleaned a number of the connectors, checked all the fuses, tested the various switches. After all that I came to the conclusion it was the delay timer. I replaced the delay timer and that fixed the problem. I was hesitant to purchase the delay timer immediately as it was the most expensive solution ate $140 with shipping.

Immediately upon plugging in the new module, the engine started in the first second of cranking and ran smoothly.

TIMER, DELAY
Item #K3211-62290
Each:$121.01

 

[KubotaZG23]

Hey thanks much for the post. Saved me a lot of time and pain and maybe a trip to the dealer. I did paid 20 bucks to down load the service manual and it was no help!!
I thought I had a bad battery and was hitting the mower with a 50 amp boost charge. Turns out the positive was almost gone. No idea how it was even trying to crank. Repaired the terminal and installed a new battery and then had the same issue you described. At the same time I noticed that the fuel gauge was fried. I let the "magic smoke" out of it.
I assume that the poor connection and the 50 amp charge threw a big inductive spike in the system.
THANKS MUCH AGAIN FOR POSTING THE SOLUTION! Many times you find folks never let folks no what the fix was.