in question is a 2002 (ancient, no?) Mercury
two stroke, 5 HP. Though I bought it new, I doubt it has 25 total hours on it. It was rebuilt after a sinking 15 years ago, and has run fine ever since until now.
I last used it 3 years ago. In preparation for an extended cruise
next year, I am tuning things up. Knowing that the carb was probably gummed up, I removed the carb and soaked it overnight in carburetor cleaner. Re-assembled it and now I trying to make it run consistently and smoothly. After fuel
is flowing (or so it seems) the engine
will crank and run wide open. Then it shuts down, after running maybe 5 seconds. Choking or un-choking doesn’t make much difference. Lotsa spark according to the spark tester, lotsa compression
, lotsa air. Obviously the problem is too much fuel
, then none at all. I can wait a few moments, crank and it does it again. Clearly it points to the carburetor. But just what?