GregP

I found the cause of my rough idle on the port motor. The bottom carb is pouring out enough gas to even fill the intake silencer. Above 1500 RPM under load it runs ok, as I guess by then it is able to pass the extra fuel without fouling out.

I pulled the carb and removed the bowl to check the needle and seat and didn't see anything obvious, but guess that is the most likely problem.

What else would cause it to pump fuel out of the bowl that I may have overlooked?

I looked at the reeds and can't see any cracked or chipped ones.

That carb both feeds the electric fuel pump for the enrichening solenoids, and gets the return loop fuel. Could a bad pressure regulator on the return loop be letting it overpower the design pressure for the needle and seat?

I'm going to see if I can get the carb rebuilt/checked and get it back in time to be up and running again next weekend.

-Greg

GregP

With a halogen light and magnifying glass (it's a b*tch getting old) I was able to see some junk in the seat that was keeping the needle from sealing. It was too big to have come in through the seat opening, so must have been floating around in the enrichment circuit, which feeds and returns to that carb. I'll have to be on the lookout for any more junk, but at least now I now the symptoms and what to look for.
I'm going to replace the needle if I can get one since it does show a wear line, the seat looks to be non-servicable. And of course I need to get some more Yami fuel line to replace the segment that cracked getting the carb off the other motor to test.

Boats are always so much fun....

-g