Newby in the house.

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Nov 13, 2017
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Hello everyone. I am trying to refurbish my Craftsman ZTS 7500 to sell for a few bucks. It is a 50 in, w/ a 24 hp B&G motor. I have a general B&S engine question. Maybe someone can stear me to the correct forum group. The question is related to the magneto coil. I can hardly see a spark at all going to the plug. I checked the continuity of the black wire going to the single post on each coil with ground and it is grounded. I checked all of the safety kill switches and they seem to be working correctly. Based on the wiring schematic, the purple/white bundle that goes to the M lead on the ignition module should only be grounded if key is in off position or one of the safety switches is grounded as per correct function.

I purple/white is also separated from ground via the seat switch, which has been cut. The plug has a fail safe contact closure when unplugged, but there is not fails safe for wire cutters. Anyway, I pulled the coils off and check the continuity between the one post going to the black wire and the body of each coil. There is very little resistance here on both. Since the metal screw that secures the coil to the top of the engine are in contact with the metal body of the coil and are being threaded into grounded metal receiving threads, the coil will always be grounded irrespective of whether the black wire is plugged in or not. From my reading of the wiring schematic, this should not be the case, b/c the kill mechanism is via grounding the black wire, thereby causing the energy of the coil to discharge through the black wire instead of the spark plug. Therefore in my case, it will always discharge through the screw.

Am I reading this correctly, or is the back wire on the coils not a kill ground?
 
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Catherine

LawnWorld Support
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Jun 13, 2015
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:welcome:

Welcome to the forum!

I'm going to move your thread over to our Craftsman section :smile:
 
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