what causes gas to pour out of overflow on bottom of carb?

[Yamaharidah420]

im gettin ready to pull my carb jus wondering what im lookin for....
Probly a stuck float right? thanks

[TLC]

YouTube - how motorcycle and atv carbs work

[justme23005]

probably a piece of dirt in the needle valve. or bad needle valve.

[stendori]

float not set right, dirt under needle, bad needle or seat.

[sprayedgt]

99.9% of the time it's the o-ring that is on the needle valve assembly. It seals the top of the assembly from the bottom and makes the fuel only go through the opening in the valve. When it fails the fuel not only goes through the opening, but around the assembly, filling the bowl, overflowing into the head and out the vent.

[JeffinTD]

Float valve/seat failure, as mentioned above, is the most likely cause.

A blocked tank vent can allow fumes to build enough pressure in the tank to push gas past the float valve.

On some carbs that include a primer knob, the seal on the primer piston can deteriorate which will also result in the carb overflowing.

[tyler1blaster]

its the float.... most likely. if you do a wheelie and rest it on the grab bar you'll see gas drippin out..