Rebuilt carb. Those updrafts are finicky, but stopped the leaks and got her to idle and rev. :thumbsup:
Like everything else on this machine, I had to learn something new. Flow Jet Carbs. You have to remove the high speed jet, then insert a common (flat head) bit into the hole and remove the emulsion tube "before" separating the carb bowl from the top. Otherwise, it will bend.
The emulsion tube in this case was corroded into the aluminum threads-a common problem. Had to EZ out it, but the threads were too far gone. Since I had a spare float section, I used it and the old jet and tube. But I used the stripped one with valve lapping compound (fine) to clean the seat. A leak there is common as well.
I applied both gas tape, (the yellow stuff) and plumbers sealant to the threads on the high speed jet to keep it from leaking. There is a direct passage from the float bowl to those threads, which is how the fuel gets sucked back into the upper section via the emulsion tube. Thus, the threads hold the fuel that is sitting in the bowl.
On the replacement lower bowl section is a 1/4 20 bolt that holds the air filter mechanism on to the carb, as well as a spring plate. I stripped that. For now, I used JB weld and it's holding, but later on I will install a helicoil in it.
Lastly, the separation point between the upper and lower sections is almost always warped. I tried everything to get it fair, to no avail. So I used JB weld again as a gasket sealer (paper gasket) and that leak stopped as well. All total, I was dealing with three leaks in all of the usual places these things occur.
The engine runs well, sounds smooth and well built, and has not a trace of smoke, which doesn't surprise me, since it's rebuilt. Learning curves. Next I'll figure out the throttle linkage. I removed the governor, since that's who the gotes were set up I think. I'm a bit nervous about that, and may end up hooking it back up.