Outdoor Power Equipment and Small Engines - Another Craftsman

I have an older Craftsman GT model 917251550 with a Kohler CV22S engine. It quit running mid turn and I initially thought it out of fuel , it wasn't. replaced fuel pump because it would try to fire AS I RELEASED THE KEY.after I found that the pump was not the issue i started the troubleshooting that I should have done initially.I have downloaded the Kohler manual. When I attempt to start the engine I get spark on both plugs WHEN I RELEASE THE KEY, and then not every time but most of the time. I disconnected the "kill" wire without changing the outcome.The Smart Spark has 12vdc at the red feed wire.I ohmed the coils no shorts or opens though 1 coil was out of range a bit. I suspect it is the Smsrt spark unit but have no tester nor do i know where i can get it tested locally.I'm not sure where I could even purchace one. any ideas ??

Test for voltage at the red wire when the key is in the start position. Could be a problem with the key switch not providing power to the ignition circuit when cranking.

I have 12vdc at the red wire feeding the Smart Spark ASAM module with the key in the on position, thanks

I have 12vdc at the red wire feeding the Smart Spark ASAM module with the key in the on position, thanks

I don't mean the on position, I mean the START position. If you are only getting spark when you release the key from the start position, could be there is no power to the SAM when cranking the engine. Once the engine starts and is running, power to the SAM is supplied directly from the charging system.

Looking at the wiring diagram for the Kohler engine
http://www.tulsaenginewarehouse.com/catalog/kohler/twin-wiring2.jpg

There are three wires coming out of the SAM which don't go to the ignition modules. The black one is ground, the red one is battery voltage, and the other one is the ignition kill lead. Disconnect the kill lead and see if the engine will start.

If it does, the problem is in the keyswitch or wiring. The ignition kill lead on terminal M is being shorted to ground when the key is in the start position.

You'll need to reconnect the wire to stop the engine.

Checked the red SAM feed wire 12vdc in on position and 9.4vdc in the start position with engine turning. white kill wire disconnected has no effect. built a spark tester ( no good deed goes unpunished ) first test right side was intermittent ( this was the coil that ohmed too low on the kill to ground test) and left fired like July 4th. second test both dead. will attmpt again Friday when I am off work. Thanks for the assist.... :cool:

9.4 volts sounds OK for when the engine is actually being cranked.

I'd completely disconnect the magnetos one at a time to see if it'll run at all on one or the other. Sounds like the right side may be bad, and it's pulling the left side down with it.

One bad module can affect the operation of the other module, isolate and test each module individually.

30YT,
I'm curious about the Smart Spark system, and maybe you can answer my question.

Will the ignition modules work at low speed if you don't have 12 volts to the SAM? Will they work with all the wires from the SAM disconnected from the ignition modules?

There's an item in the Kohler troubleshooting about backfiring at high speed being caused by a blown fuse in the SAM. That makes me think the ignition module can work at low speeds without the SAM, but it needs the trigger from the SAM to get the timing right at high speed. Is that what's going on?

roger,
I believe you are correct, at least thats what I understood on the older SAM equipped engines, although I have never tested it out on an engine to see if it would in fact start and run this way. I seem to recall reading somewhere that there was a way to convert a SAM equipped engine with modules that eliminated the SAM.

isolated the coil modules ( pulled trigger & kill wire off alternate sides) left side shows spark ( not great but consistant) right side ( coil nearest ASAM ) deader than a hammer.so I hooked up the left side trigger and kill to the right side coil and no change.If i were prone to assumptions ( ie fuel pump) again, i would suspect that the right hand coil was shot.:cool: any words of wisdom???

found coils online for about 30 + 6 s&h should I replace both of them ?? thanks for your input.. :cool:

I'd replace just the right side, unless you want to have $30 tied up in a spare module you may never need.

I just looked at the listings on ebay. There are a bunch of new modules listed, some for as little as $20 plus 7 shipping. Also some used ones for less. Might be worth a look.

coil ordered. will update when it is replaced. sure hope it works.. wife is talking about the lawn mower repair guy.:eek:

;) replaced the coil today , fired up before it could even turn over one time. thanks for the help.. now anyone know much about a merc cruiser alpha1 Gen 2 outdrive ???? :rolleyes:

Glad its fixed. Thanks for the feedback tht it is fixed.