HM 80 No Spark

M

Mattmotors

Active Member
Tecumseh HM80 155128C Serial 62160
coil 30560a points 30547a condenser 30548b
My ariens has a no spark situation. So after 47 years I decided to replace the coil, points and condenser. The new points and condenser are OEM. The coil is an Oregon. Put it back together, still no spark. The way I did the final test was the following:
The only wires on the points stud was the coil wire and condenser wire. (no safety switch wire at this time.)
Other coil wire is connected at the condenser mounting bolt .
Both magnets on the fly wheel are strong. (screw driver test)
mounted fly wheel and hit the electric starter. No spark.
When I removed the mag plate, I marked it so it went back in the same position.
I Have a Stevens tester for outboards. The condenser is perfect, The points are less than 1 ohm and the points stud is not grounded. Points are set at .020 on the high side.
Both the old and new coil test very similar electrically with an ohm meter.
No wires are pinched.
I'm stumped. Is there a new OEM part number for the coil?
Please share your thoughts. I'm going back to the pole barn to have a stare down match. Thanks , Matt.
 
I think I found my problem. I just need some confirmation and how to fix it. when I test for spark with a neon tester, it flashes like crazy. When I do the spark plug test....nothing. Then , I had a good look at my fly wheel. Magnets. Look at the 2 flywheels. Mine and one for sale on ebay. Ebay is the first one. It looks like one of my magnets came loose and attached it self to the other one. It makes sense to me why I lost the spark.I thought they were suppose to be like that. When there is a no spark situation, the last place I would think to look is the fly wheel. What should I use to re attach the magnet.Thanks , Matt.s-l1600.jpegIMG_4784.jpeg
 
Some people try reattaching the magnets, but I’ve never had any luck doing so. It’s up to you if you want to try.
 
Are you sure the ignition magnets aren’t on the outside of the flywheel? My current fleet of HM80 engines’ flywheels have magnets on the outside for ignition. Set the coil gap to the flywheel with a feeler gauge at .009-.012”. Points at .020” is perfect.
 
You may have this resolved already, but I will reply anyway for anyone else who runs into problems with glued flywheel magnets.

Mark exactly where the magnet came loose. Mark the magnet(S) for correct orientation because they have a north and south pole that have to be correct. Clean the area well but not so clean you lose your reference location area.

Get some High temp JB Weld and mix a little bit of it according to instructions. Apply a thin layer to the back of the magnet (just enough to squish out), then clamp it into place and let it fully cure for 2 full days. (personal preference).

I have epoxy glued many flywheel stator magnets back on and never had any issues.

Taryl Fixes All on You Tube has a good video about how to do this.


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Epoxies on smooth surfaces can sometimes struggle to adhere. A clean surface is imperative; scuffing the surfaces after cleaning (and cleaning after scuffing) is a good idea. I personally have never had magnets come loose though; I took some notes in case I ever do.
 
A lot of the Kohler and Kawasaki engine have the stator magnets come off with age. I have pulled a number of flywheels, and all of the magnets were stuck to the stator. I think the extreme heat down here in South TX has a lot to do with them coming loose.

From the factory, they are bonded with a yellow or clear contact cement glue.
 
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