Why is My Honda ATV Carburetor Leaking?

When your Honda ATV is leaking oil into the carburetor and/or fuel is seeping through the hoses, it's time to do a carburetor rebuild or replacement. 

Our resident Honda ATV expert John Talley livestreams on our YouTube channel every Friday at 3pm Eastern. In this session, John addresses one of our viewer's concerns with a Honda TRX400 experiencing oil and fuel leaks at the carburetor.

Honda ATV oil and fuel carburetor leak

Honda ATV Carburetor Leaks

The petcock on my Honda 400EX leaks oil into the carb, even with the knob turned off. Time for a new petcock? Also, the gas goes through the hose at the bottom of the carb. Time for a new float valve? 

John Talley: I think you just nailed it. That machine has some years on it, so you’re already pointing in the right direction. The petcock basically has a window where you’ve got two O-rings inside of it, and those O-rings start to break down and most of the time they just stay on all the time. Now as far as your carb overflowing, that’s the float bowl seat or the valve itself is probably cracked or worn out. Hopefully it’s not the seat and you can just replace the shutoff valve itself. If you’re going through the carb and you don’t want to do it piecemeal, I know that Moose makes carb rebuild kits where it’s got all the right gaskets. Because chances are when you open this up, you’re going to create some more problems with gaskets and O-rings that may be sealed right now, but they’re not going to want to reseal when you put it back together. So just be prepared to at least get the gasket or the O-ring for the float bowl when you drop it, because chances are it’s going to need to be replaced if you’re just going to do the needle for the float bowl.

Buy QuadBoss carb rebuild kit for Honda ATV

Buy ATV carburetor

Watch the video below to see how to clean the carburetor of a Honda TRX400 ATV.

Watch the video below to learn about whether it's time to clean, rebuild or replace a carburetor.

Want to see more live repair questions answered? See more motorcycle and ATV repair questions answered here.  





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