I am recommissioning our 1989 Yamaha and got it up and running with a complete carburator cleaning. It runs great, but leaks a little fuel out of the float bowl drain. I lightly polished the needle chamber and triple checked everything. Still weeps, so I ordered up a new needle and bowl gasket from Babbits and thought I solved it. Still weeps. Dang it! I am at a loss as to the cause. I checked to see that the float actually floats and it does. Anybody here have a similar experience and found a solution? Thanks!
Yamaha Zuma Prebug Carburator Help
- Thread starter t6dpilot
- Start date
Chainlube
Well-Known Member
The float could be a little high, but most likely the needle gets stuck in the seat. Look very closely in the seat (magnifying glass) for any kind of obstruction, and the needle itself, might have a bad tip.
Thanks for the reply. I will take another look at the needle seat. I polished it and the chamber with metal polish to remove any obstruction. I'll look at the needle too, but it is brand new so don't suspect that to be the issue (and it looked fine initially). I wish I could find a drop in replacement carburetor for the Prebug Zuma.
Chainlube
Well-Known Member
The needle can be held open with a small piece of grit, I had that happen to one of my SUs on my spitfire. Took me days to figure it out, it just kept coming the overflow and just got the car running and was reluctant to revisit that just then.
Post a picture of the carb, there probably a replacement for it. Most likely a PZ19 or VM18, if it's a 50cc.
