Kohler engine no spark till coasting.

mcostello

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Busy tonight, will begin diagnostics tomorrow, thanks.
 

mcostello

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I have checked the ignition switch and all works correctly. Black wire from switch ends up on the + positive side of the coil. With a test spark plug grounded to the engine there is no spark when cranking, VOM meter confirms this. When letting off the key there are several strong sparks shown.
I have done a little looking around and found no evidence of crossed wires. I don't know how many safety switches there originally were. There is only one on the hydraulic transmission and it works as expected. Where to proceed?
 

ILENGINE

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So you are saying that you have battery voltage at the + side of the coil while cranking the engine but don't have spark.
 

VegetiveSteam

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If the answer to IL's question is yes, is the black wire from the switch the only thing connected to the + terminal on the coil?
 

mcostello

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Did not check voltage to coil, just checked spark. Black wire is the only thing fastened to the coil RIGHT THERE. Every thing else is hidden under the battery tray. Will check these tomorrow. Thanks for the ideas.
 

VegetiveSteam

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Did not check voltage to coil, just checked spark. Black wire is the only thing fastened to the coil RIGHT THERE. Every thing else is hidden under the battery tray. Will check these tomorrow. Thanks for the ideas.
No need to check. Sometimes when points and condenser get replace a person might connect the condenser to the + side of the ignition coil and that doesn't work.

You probably have no voltage to the coil while cranking. Just a thought but has the ignition switch ever been changed? If so and it happened to be replaced with a switch for a magneto ignition that will cause issues. If you time it just right, they can work but over time things can change. With most magneto ignition switches, the run terminal goes dead when you turn to the start position. On an ignition switch for battery ignition, the run terminal will stay hot when you turn to the start position.
 

mcostello

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The switch has not been changed in My time with it. It is a 1978 model - 46 years old. I have only had it 2-3 years. More troubleshooting. Thanks, Mark.
 

ccheatha

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Just wondering, was this the first and only symptom? Prior to this, was there no rough running, bogging down or anything like that?
 

StarTech

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So you think nothing never wears out?
 

VegetiveSteam

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Run an unswitched hot wire directly to the + side of the coil. If the engine starts and runs fine, you know all of the ignition components are fine. Now just find out why you aren't getting power to the coil while cranking.
 
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