Tecumseh 8HP engine won't start

Thie engine on my John Deere 828D walk-behind snowblower will not start. I have run this engine at least weekly (even in the summer) for 9 years since it was brand new. I just changed the oil 1 month ago. Two days ago I went to start it and she wouldn't turn over, no spark. I just replaced the spark plug (yes, I gapped it at .030 per spec), and still there is no spark. Whether I try to pull-start it or use the electric start, the flywheel turns,but no spark at the spark plug. (Yup,I pulled the plug out, grounded it and no arc when I used the electric start). Now before i start following the ignition wire, I'm going to assume it goes to a magneto. Ironically, this past spring, I had to replace the magneto to my John Deere 155 riding lawnmower because of no spark, so I am quite aware of the magnet on the flywheel, the gap, etc.

Now before I start doing this, because I can't locate any online service manuals, is there any suggestions of what the problem may be if it isn't the magneto. Or any other suggestions. Any input would be greatly appreciated. Thanks.

 

The magneto is my thoughts too,as well as maybe a shorted kill wire.

 

where exactly would this kill wire be. pointing me in the direction of what part of the engine it would be located would be helpful. thanks.

 

The kill wire would run from the coil/module to either an ignition type key switch or a kill contact on the throttle. There are some engines that have the igniter which is a small box affair wired to the coil. To isolate the kill you would disconnect the wire just after the igniter going to the kill switch. If no igniter, you would just disconnect the wire at the module.


I'm not sure if Tecumseh even used an igniter. It seems like the Kawasaki models did though.

 

ok....update......the magneto was off a bit to the magnet on the flywheel. there was .010 gap on oneside, and .021 gap on the other. i'm not sure of what the gap is supposed to be exactly, i can't locate the specs on this online, but i'm going to go out on a short limb and say between .008 and .012 because this was the recommended gap on the magneto to my john deere lawnmower and these magnetos are very similar. but if anyone knows exactly, please do tell me.

anyways, i even out the gap and made it .010 on each side of the magneto to the flywheel magnet. sometimes i get a spark and can get the snowblower started, sometimes i couldn't. the kill wire looks fine, no short with it from what i can see. i'm going to assume the magneto-coil module with ignition wire is just getting weak and needs to be replaced.

now one last question. is there anyplace anyone knows offhand besides a john deere dealership where i can find this magneto. trying to find the best deal out there. thanks again guys for all your help.

 

The air gap of .010 is pretty much standard. Most use a business card as a gauge.

Turn the magnets away from the module, slip the card between the coil and flywheel, turn the magnets to line up with the coil, let the magnets draw the module down, tighten the mounting screws, turn the flywheel magnets away from the module and take out the card.

Disconnecting the kill wire is to not only take the wire out of the equation, but the kill switch as well. Sometimes the latter causes problems.

If you're replacing the module, a lot of the guys here with shops will say to stay away from the aftermarket modules and go OEM to avoid problems.