OK, so here we go again. Last Fall I had trouble with this Sears two
cycle leaf blower, where it would not start. Finally figured out it
was a stuck piston ring. The ring broke when I tried to get it out,
so I cleaned up the groove with a tiny screwdriver, got all the carbon
out, got a new ring, put it in. In floated freely. Put it back
together and it ran fine for awhile, then I had carb troubles. So,
I bought a new carb from China and it ran better than when it was
new. I put maybe 8 hours of use on it last Fall. Now it won't start
again, won't fire.

After exhausting all possibilities, I took it apart again and the
piston ring is stuck again. Sides of the piston have some black,
shellac like stuff on it too. Broke the ring again, but have it
all cleaned up again. The question is why did it foul again?
Some more history, when this was new ten years ago, I should have
taken it back, because it didn't run well with no choke. So most
of the time on it, I ran it with half choke. Of course if they
had screws you could adjust, I could have tuned it, but instead I
just put up with it. So, first time the ring got stuck, I figured
it was probably from running it too rich all those years. After putting
the new ring in, I probably ran it for a few hours with the old carb
and half choke. But after that I put the new carb on and it ran
beautifully, no choke. I made sure to use a modern synthetic oil,
mixed to the correct ratio. So, how did it get fouled again in just
8 hours? I know I should just put it out into the dump, but it's
otherwise in fine shape and runs great when it runs and this has become
kind of a battle of wills.