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Stihl HS80 engine rebuild spark help /advice

WDC1

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After rebuild where I installed a new Stihl OEM carburetor and coil. I'm having a spark issue. I set the coil gap using a business card as I've done many times before. The problem I'm having is there is spark when using the old spark testing tool which looks like a flashing neon light indicating spark. When I insert a new plug as well as the old plug. I cannot get a spark through the spark plug. Advice or suggestions would be appreciated.

Why would I have a spark indication test tool but not through the spark plug? Is it a possibility of two small of coil gap?

Whereas I've never had a problem with the business card method when gapping the coil for precautions. I just purchased two Stihl OEM COIL GAP GAUGE SETTING TOOL.2mm - 4118 890 6401 as well as a .35mm 1127-890-6400. Since I read that the coil gap should be between .2 and .5.
 

GMB74

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Coil gap is important, but not THAT critical. A business card should work fine. Pull off the boot and check the wire end that attaches to the sparkplug. Has it popped out of the coil wire? Corroded and causing a bad connection?
Is there a ground wire from the frame to the coil that is loose/corroded/missing?
Maybe a weak coil? Rig up a spark tester by opening up a sparkplug electrode about 3/16- 1/4 inch. Or buy a commercial spark gap tester. Make sure you have a good ground and test in a dimly lit area. A good coil should jump that gap.

Also try disconnecting the kill wire at the coil and retest. A chafed wire or goofy shutoff switch could possibly cause a weak spark.
 
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