Husqvarna 125B won't start, no spark.

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chainsawdave

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My Husqvarna 125B won't start, has No Spark. I haven't yet disassembled to look at Kill Switch but while I am in there I will check the Flywheel-to-Coil gap, Coil Resistance and possible Sheared Flywheel Key.

4 Questions:

1) Should Flywheel/Coil Gap be the usual Business Card dimension?

2) What should Primary Coil resistance be? What should Secondary Coil resistance be?

3) I have the Operator's Manual. Anybody have a link to free Shop/Service Manual?

4) Also, for No Spark condition is there anything else I should diagnose/Test? (Ex: Condensor, assuming Flywheel Gap, Flywheel Key and Coil Resistance checks are OK/Passing)?

Thanks for any input.

Dave
 
My Husqvarna 125B won't start, has No Spark. I haven't yet disassembled to look at Kill Switch but while I am in there I will check the Flywheel-to-Coil gap, Coil Resistance and possible Sheared Flywheel Key.

4 Questions:

1) Should Flywheel/Coil Gap be the usual Business Card dimension?

2) What should Primary Coil resistance be? What should Secondary Coil resistance be?

3) I have the Operator's Manual. Anybody have a link to free Shop/Service Manual?

4) Also, for No Spark condition is there anything else I should diagnose/Test? (Ex: Condensor, assuming Flywheel Gap, Flywheel Key and Coil Resistance checks are OK/Passing)?

Thanks for any input.

Dave
I know you probably have but try another spark plug! The simple things first.
 
I always use an Adjustable Gap Spark Tester. This is better than testing using another sparkplug because it yields quantitative measure (I learned this the hard way working on outboard motors).

I will look for pinched wire.

Thanks for the input.
 
Been a while since i got back to working on this. Changed spark plug, it ran for a few seconds then quit. Installed new carburetor. No go. Seems like it is getting no spark again. Don't see evidence of pinched wire.

So (before i swap parts again blindly, i.e. without doing proper diagnosis) what should the Primary Winding and Secondary Winding resistances be? Also, what is recommended gap Coil-to-Flywheel? Using a adjustable Spark Gap Tester how much gap should spark jump?

Amy input is greatly appreciated.

Dave
 

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