Fuel leak at main air jet

[Tysons87venture]

Hey guys, I am wondering if anyone has ever experienced fuel coming out of top of carb main air jet? If you how did you fix? I have adjusted float, tried new float valves and no matter what I've tried everything fuel just keeps coming out top of carb

[cimmer]

you might want to check the rubber plugs that fit in the bottom of the jet block. They should be a very tight fit and tend to get hard over time.  Yamaha still has them listed on the parts list and being available..  check out this link and the items are 41 and 43. FYI ..  You will need one of each for each carb.   https://www.partshark.com/oemparts/a/yam/5107f835f870022108d6576a/carburetor-non-california-model

What happens is when they are loose is that fuel will get sucked up past them and add more fuel then the jet will allow.  This is often overlooked and can cause the issue you are talking about.

Good Luck and let us know if this helped you out with your issue.

Rick F.

Edited September 25 by cimmer