# Husqvarna 125B won't start, no spark.



## chainsawdave (Oct 16, 2019)

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


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## grizz55chev (Oct 16, 2019)

chainsawdave said:


> 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:
> 
> ...


I know you probably have but try another spark plug! The simple things first.


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## buzz sawyer (Oct 16, 2019)

Had a similar problem on my 128 trimmer - spark plug wire was pinched. Someone else had been into it in the past.


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## chainsawdave (Oct 16, 2019)

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.


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## chainsawdave (Apr 22, 2020)

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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