Originally Posted by walkinman

I've got an old Mac 2816 that has no spark. Initially I tried changing the spark plug with no result. Next I disconnected the kill switch, (which had a small fray on the insulation of the wire going to it. I still got no spark when I cranked it. At this point I suspected either a worn or sheared flywheel key or a faulty ignition module. Both the key, and the keyway were in good shape, showing no wear, or deformity. Finally I was able to find a new ignition module for the machine, (no small feat in itself), but after swapping out the old one, I still have no spark.
Since I had the recoil start housing off the machine I spun the engine using an industrial electric dril at approx 175 rpm.
It's a pretty simple circuit, with no interlocks or anything that I'm aware of. As a result, I'm stumped. Does anyone out there have any new ideas I can try?

Have one of those old Mac's myself...may sound stupid, but are you SURE the spark plug wire doesn't have an internal break between module and spark plug boot? Use a spark tester to see if the module is putting out voltage but the wire isn't conducting any.