55 Rancher -- diagnosing no spark

[mikeccb]

My boss gave me an old 55 Rancher that doesn't have spark, and I'm having a hard time figuring out why.

The spark plug is good (it works in another saw). I believe the ignition module is good (resistance between the body of the ICM and tab is ~1.5 ohms, and resistance between body and plug end of connector is ~6.5K ohms. Air gap between ICM and flywheel is a business card. And I have no spark even when the lead to the kill switch is removed from the tab on the ICM. There are no other wires.

Is it possible for an ICM to test OK but still not work? Am I grounded somehow? Flywheel magnets not strong enough? Anything else I can check?

Many thanks!

 

[cscltd]

Ignition modules can show perfect resistance/ continuity and not produce spark.

 

[mikeccb]

Ignition modules can show perfect resistance/ continuity and not produce spark.

Thank you for the info, I didn't know that there was more to them until now... Much appreciated!

 

[lone wolf]

Check where in the spark plug boot goes on the spark plug. Make sure the connector in there is going into the hi tension lead properly. If all good there the coil is the next logical thing to be replaced.

 

[mikeccb]

Check where in the spark plug boot goes on the spark plug. Make sure the connector in there is going into the hi tension lead properly. If all good there the coil is the next logical thing to be replaced.

Thank you! I did test that with a meter and had an acceptable resistance from the body of the coil to the connector in the boot (and to the tip of the plug when it was installed in the boot).

I will order a new coil -- thanks again

 

[Chevboy0167]

And IF you decide to purchase a module, try a used OEM original Husqvarna one first! Or buy new if you like.

Many aftermarket are NFG..... Case in point, this saw had perfect blue/white spark on a new plug outside of the cylinder. Installed it had NO spark under compression.

It was a brand-new unit from the usual scumbags...... I got a used OEM from eBay for $10 and a bit of shipping. Popped off right on the second pull and still running to this day.

 

[lone wolf]

OP you might be able to get a used one on this site from a member if you post a wanted ad. click link .

https://www.arboristsite.com/forums/tradin-post.132/

 

[river of smoak]

I had just finished rebuilding a 55 rancher and it was a no start , no spark . ended up being a crap connection from the plug wire to coil .

 

[lone wolf]

I had just finished rebuilding a 55 rancher and it was a no start , no spark . ended up being a crap connection from the plug wire to coil .

Does the coil wire on that one screw into the coil, or is it permanent?

 

[river of smoak]

mine unscrewed , has a pointy spike in center of coil tower .

 

[lone wolf]

mine unscrewed , has a pointy spike in center of coil tower .

He could try tightening that.

 

[river of smoak]

thats pretty much how I got mine to work . took it apart first and tried to center the center of the plug wire with the spike