ZG23 w/ Kohler CH23S has no spark

   / ZG23 w/ Kohler CH23S has no spark #1  

TruChaos

Silver Member
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Apr 18, 2004
Messages
197
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 need to be replaced?
 
   / ZG23 w/ Kohler CH23S has no spark #2  
Could you supply the Specification number from the model number tag. Serial number of the engine would even be better from a dealer such as myself standpoint to I can look up the exact built on the engine. This engine has two ignition modules, but depending on which ignition system configuration could also have a SAM aka Spark Advance module, Looks like plastic black box mounted on the side of the engine with a clump of wires going under the blower housing. But you could also have the DSAI system which doesn't have the external SAM box.

There as a few built that used a fixed timing ignition system.
 
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   / ZG23 w/ Kohler CH23S has no spark
  • Thread Starter
#3  
Could you supply the Specification number from the model number tag. Serial number of the engine would even be better from a dealer such as myself standpoint to I can look up the exact built on the engine. This engine has two ignition modules, but depending on which ignition system configuration could also have a SAM aka Spark Advance module, Looks like plastic black box mounted on the side of the engine with a clump of wires going under the blower housing. But you could also have the DSAI system which doesn't have the external SAM box.

There as a few built that used a fixed timing ignition system.
Family: 4KHXS.7252GC
Displacement: 674
Model: CH23S
SPEC No.: 76582
Serial No.: 3402003861
 
   / ZG23 w/ Kohler CH23S has no spark #4  
Family: 4KHXS.7252GC
Displacement: 674
Model: CH23S
SPEC No.: 76582
Serial No.: 3402003861
Looks like that engine is using the fixed CDI ignition modules. So remove the blower housing unplug the white wire from the modules and see if you have spark. Module part number is 24 584 45-S and should replace both modules due to changes over the years and two different part number modules may not be compatible with each other.
 
   / ZG23 w/ Kohler CH23S has no spark
  • Thread Starter
#5  
To remove the blower housing, the engine has to be removed from the mower. It's in backwards with the housing between the engine and the bulkhead behind the seat.

I fixed the problem. I cleaned the connectors, checked the switches (replaced the brake switch), swapped out new relays, etc. Nothing fixed the problem. I came to the conclusion that the problem was the delay timer. I was hesitant to purchase it as it cost $140 with shipping and is non returnable. But after eliminating everything else, I bit the bullet and bought the module. That fixed the problem. Now, instead of cranking endlessly to start, it fires up immediately and runs smoothly.

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