[centuryhouse]

I don't have a timing light but plan to get one on payday.

I advanced the timing to various degrees, and retarded it as well, but neither resolved the issue. It seemed that where it was originally was the best place, based on idle speed, how the engine sounded, and how the exhaust looked/smelled.

I don't remember the gap of the plugs, but I researched it here when I did it and used the most commonly recommended plugs and gap.

Why get rid of the glass filter? I just paid extra specifically to get one, rather than the plastic or metal kinds I had. I wanted to be able to see what was going on. This filter was $16 instead of $4 for the other types.

The observation that the engine is probably late 70s - early 80s is probably correct, based on their telling me (when I bought it) that the engine had been replaced in the 80s. It makes it hard to buy parts that fit.

I am somewhat mechanically handy, though a little intimidated at the idea of a rebuild. I could buy a new carb. It seems I'd have to be able to adjust the mixtures and fine tune it no matter which course I take, and I don't know anything about doing that yet.