CubCadet 1720 no spark

oldnslo · Mar 28, 2021

Engine is Kohler MV18S opposed twin:
Crankcase was full of oil and gas mixture so drained the oil, refilled with new oil. Engine started and ran fine while I looked for any gas leaking around fuel pump and watched for evidence of carb over flowing. After running for several minutes shut engine and loosened carb mounting bolts to check for gas dripping from carb. Let sit for couple of hours and gas was dripping slightly from carb and bottom of fuel pump looked wet so decided to replace fuel pump and float needle in carb. Reassembled everything and now no spark. I removed ground - kill wire from ignition and still no spark on either plug. Tried different plug with same results. Can the ignition module just fail like this? Not sure what else it could be since ran fine prior to shutting down to fix fuel concerns. I never turned the engine over without one of the plugs installed in the head and wire connected.

Roadworthy · Mar 28, 2021

Yes, the ignition module can just fail like a light bulb can just fail. You could also not be getting power through the ignition switch or possibly even one of the safeties is not being satisfied. Maybe a ground is not firmly attached. I'd do some further troubleshooting before giving up on the ignition module.

oldnslo · Mar 28, 2021

I believe this is a magneto style ignition system so no power from battery required and with ground-kill wire removed all safety switches should be eliminated but I certainly could be wrong in this presumption

Richard001 · Mar 28, 2021

You can get a copy of the Kohler MV18 service manual here:

http://resources.kohler.com/power/kohler/enginesUS/pdf/tp_2289_a.pdf?_ga=2.134928113.1071892200.1616979590-1757437663.1616979590

Richard

Richard001 · Mar 28, 2021

This ignition system is a wasted spark system, so if one plug is bad (shorted), there will be no spark on either plug. Check your plugs.

Richard

oldnslo · Mar 28, 2021

Richard
Thanks for the link to the service manual.

oldnslo · Apr 1, 2021

update, ignition module met all of the resistance tests listed in service manual but still no spark so bought new module and now have good solid spark.