Kohler Two Cylinder Engine with no spark.

[grawolff1]

I have an older model L130 John Deere with a Kohler engine. I have been all though it and it comes down to this. If I connect the kill cable to both of the coils, I get no spark. Remove either connector and I get a good strong spark. If they are connected together, there is no spark. Even if I disconnect the kill cable from the rest of the wring and only have the cable connected between the two coils. One coil was eaten by mice (again) so I installed a new one. The other one is only a couple years old. It stinks of mouse house, but it still works. I've cleaned all the contacts and replaced the eaten wiring. And, of course, I have removed all of the mouse's living quarters as well. So I can still use the mower and to be able shut it off, I cut the wire between the two coils and installed a kill switch that reconnects them when pressed.

Has anyone else had this same electrical issue or have any thoughts on what is going on?

Any advice on keeping the mice from eating my mower ever year would be appreciated as well. This time they even got the deck belt.

 

[hlw49]

●Engine Cranks But Will Not Start. Diode in wiring harness failed in open circuit mode. Right out of the Kohler repair manual.

 

[grawolff1]

●Engine Cranks But Will Not Start. Diode in wiring harness failed in open circuit mode. Right out of the Kohler repair manual.

Thank you! I had an idea that the diode might have something to do with it when I looked at the wiring diagram. I wasn't aware there was one in the harness. I removed what was chewed and replaced it with plain wire. I don't have a repair manual. By any chance does it give the specs on the diode or a part number?

 

[grawolff1]

●Engine Cranks But Will Not Start. Diode in wiring harness failed in open circuit mode. Right out of the Kohler repair manual.

In case you have access to the specs or part numbers. I'll try the Kohler site. Thanks again!

 

[bertsmobile1]

Kohler put the diode in the magneto coil , not external as per B & S
So of course you have to replace a $ 50 magneto in place of a 50¢ diode

 

[StarTech]

The diode referred to in the service manual is the two that power the anti after-fire carburetor solenoid. They also feed the DSAI coils if present. Note these are no longer available and must be upgraded to the standard CDI Fixed coils. Easy enough to find if they are good as the carburetor solenoid will click when they are good.


But what being described here is the failure of the internal steering diode in the ignition coils. Can be one or both coils has the diode shorted. Usually both coils has to be replaced or you can try installing a Briggs style kill harness with external diodes. This something I have yet to try out but in theory should work. Should be able to use a pair of 1N5408-G diodes. Connected so each coil does not backfeed the other coil. The anodes should connected to each coil with the cathodes connected together so when they are grounded the ignition coils are killed.

 

[grawolff1]

The diode referred to in the service manual is the two that power the anti after-fire carburetor solenoid. They also feed the DSAI coils if present. Note these are no longer available and must be upgraded to the standard CDI Fixed coils. Easy enough to find if they are good as the carburetor solenoid will click when they are good.
View attachment 61326

But what being described here is the failure of the internal steering diode in the ignition coils. Can be one or both coils has the diode shorted. Usually both coils has to be replaced or you can try installing a Briggs style kill harness with external diodes. This something I have yet to try out but in theory should work. Should be able to use a pair of 1N5408-G diodes. Connected so each coil does not backfeed the other coil. The anodes should connected to each coil with the cathodes connected together so when they are grounded the ignition coils are killed.

EXCACTLY what I needed. Unfortunately, I only have 1N5401 diodes in my kit. Keeping in mind how long I've spent on this issue so far, I'm buying new coils instead of cutting in the diodes. I'm not a fan of Disney anyway so I won't be Mickey Mousing this one. Amazon has a few coil sets with 4.5 stars and above and I can have them in a few days. Thanks!

 

[grawolff1]

Kohler put the diode in the magneto coil, not external as per B & S
So of course you have to replace a $ 50 magneto in place of a 50¢ diode

I suspected that since there was no evidence of one in the coil wiring. I'm thinking the mouse urine permeated the coil and trashed the internal diode. The other one is brand new so I'm sure it's fine. I'm going with this set: https://www.amazon.com/dp/B08JH2VXY...jbGlja1JlZGlyZWN0JmRvTm90TG9nQ2xpY2s9dHJ1ZQ== Thanks!

 

[grawolff1]

Now about those mice...

 

[hlw49]

Yes you are right wasn't thinking. Generac use to have diodes in their kill wires and have since done away with them and put them in the coils as well.