Spark Advance Module???

[BFET529]

Hi there... I have an ignition problem that has stumped me. My craftsman riding mower kept quitting while mowing once it would get hot and was running poorly. Once hot, I would get no spark. The mower would get spark and start fine on a cold start though. Since this is a common symtom of a bad coil/ignition module, I replaced the ignition module. Motor started and ran flawless for about an hour and a half while mowing, and died. Now it won't even start cold. The motor turns over just fine. Just won't fire. I found a discussion regarding the spark advance module and tried what was suggested. I removed the white wire that comes from he spark advance module, and the mower started right up. I turned the key off and it shut off. I plugged the white wire back in and wouldn't start. What do I need to do to fix this problem? Since the motor starts and runs fine when the white wire is disconnected, does this mean I simply need a new spark advance module, or is there a problem somewhere else with that wire? I want to fix this the right way, but what would happen if I simply left the white wire unplugged? Thanks for all the help ahead of time!

 

[RandyT]

SAM module has been discontinued, will need to upgrade to the new ignition system where the spark advance is built into the module itself instead of a separate unit.

Unit will run without white wire, but will not advance timing, causing loss of power.

 

[BFET529]

Thanks Randyt,

After I replaced the ignition module itself, i realized that there was the new part that came as one, instead of two seperate pieces... Does this symptom of only running with the white wire unplugged, and not running with it plugged in, mean my spark advance module is my problem? or is there a different problem? I don't want to run it with the white wire unplugged if I don't have to... I'd rather it fixed right. That being said, I don't have any problem purchasing the new SAM part that comes with the SAM and ignition module as one part, I just want to make sure before spending the money on it, that it is indeed my problem.

Thanks for all your help!

 

[RandyT]

What is the model and spec of your engine, so I can look up the correct engine info to answer your question.

 

[BFET529]

Thanks RandyT for the help. The model number of the tractor is 917271041. The model # for the motor is CV16S and spec # 43514. From what I can deduce, the white wire is the kill wire... So I am guessing the SAM is working just fine, and that white wire is either grounded somewhere between the SAM connection and the battery, or I have a bad safety switch. By disconnecting that white wire, I think I am simply bypassing all safety features, and not actually affecting the way the motor should run... Does this sound correct?

 

[RandyT]

From the Kohler service manual, the white wire is the kill wire. I would say you have a bad safety switch or something in the kill system shorting out.

 

[BFET529]

So I think I found my problem. It looks like the white kill wire turns black, and that wire I found pinched between the frame and the motor. The insulation was rubbed off and once pulled free, the motor started like it was new. When running, i touched this bare wire back to the motor, and it would about die, until I removed the wire. As soon as the wire was removed, it would rev back up and run flawlessly. I electrical taped it up, and zip tied the group of wires away fromt he motor. I am going to mow later today, so I'm keeping my fingers crossed that I have fixed the problem. Pretty simple fix in the end of it all after a lot of frustration! Thanks for your help RANDYT!