I have been repairing small engines for quite a long time. This Tecumseh HM100 on a 6 Kw geberator is driving me crazy. It has an occasional very noticeable miss at random times. When it misses there is no fire from carb or out exhaust. Sounds like ignition.
Here is what I have done so far:
New Plug
New coil
New flywheel key and checked flywheel for cracks etc
Checked flywheel magnets with screwdriver test and it snatches screwdriver nicely.
New carb, filter fuel lines and fuel shutoff in tank,
Lapped valves checked seats and adjusted valve clearance.
Cylinder walls still have nice cross hatch pattern on them
cleaned carbon out of head and off piston
Checked exhaust for carbon but OK
tried 2 different carbs and 2 coils with no change and set idle speed to factory specs
Using a resistor plug gapped at 30.
Seems to run a bit better with non resistor plug but not much
Set governor linkage
Spark is bright blue
In almost 30 years of working on engines I have never seen one like this. I do admit I tried to stay away from tecumseh motors most of that time as I really hate them.
Only thing left is a 45 cal shot to its head and that may be soon.
Any ideas of what I have missed. Gun is loaded and ready
Thanks
Mowfixer