Model L one pop every time but doesn't run

[CharlieNH]

Machine ran fine last year. Ran it dry at end of season. New gas now. Electric start. Pops once every time I hit the electric start, but that's it. Won't get going. Rmoved plug to observe spark. Good sparks continue as electric starter is engaged, so it's not just getting one spark when the magneto starts up. Gas getting to carb, and nothing was changed since it ran last year. Could it be a stuck valve? I hope not. I don't even know how to get at valves. Advice much appreciated.

 

[thompsonseatgrinder]

Charlie,
Just seen your post here. Do you still need help?
Darrel

 

[CharlieNH]

I've been waiting for the grandkids to leave so I can get back to this. I'll post on progress.

 

[thompsonseatgrinder]

Let me know. Somehow those grandkids have priority!! Right off though, it does sound like a stuck exhaust valve.

 

[bob11x]

It's the mag- dirty points, bad condenser or weak coil.

 

[Leejohn]

Flywheel keyway.