Johnson Lost Spark

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Keith1

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I have a 1993 Johnson 6 HP and have lost the spark on the top cylinder. The ignition coils check good on both cylinders. I have a Fluke 87 meter to check the output of the power pack but can't get it to indicate peak voltage correctly however there is an output from one of the PP leads and nothing from the other. Does this indicate that the PP is bad?
Does anyone know of a different kind of check?

Thanks and Regards, Keith
 
Typical check path is to start at one end or the other and work back.
Since you started at the spark plug and then verified coils then pack output only on one cylinder you still have at least one more check to make.
That check would be the timer base. The stored energy in the capacitor(s) in the pack is released by a signal from the timer base. This is usually only a 5V peak signal. Pretty much anything above around 1.2 or higher during cranking indicates the circuit is good.
The charge coil under the flywheel charges the capacitor(s) in the power pack at somewhere up to around 300V. We know that is working because you have pack output to one cylinder.
 
Pappy, The output from the power pack was 4.5 volts on one lead and basically 0 on the other. Do you think that indicates a bad PP?
Thanks, Keith
 
Keith1 said:
Pappy, The output from the power pack was 4.5 volts on one lead and basically 0 on the other. Do you think that indicates a bad PP?
Thanks, Keith
Reread what Pappy said and I think you will read no output from the power pack until the timer base sends the signal. Check your timer base output first. If it's good then look at the power pack.
 
I will get back with you in a few days. My Fluke meter needs an adapter to be able to work correctly and I am waiting for that. Thanks

Keith
 

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