Overflowing

[Drizzle]

Mikuni bs38. My right side carb is pouring fuel out about twenty minutes after filling it back up and riding. I pulled the float and float needle several times. Never saw a problem but bought new ones anyway. Adjusted the float the same as the left bank carb and installed it, new seat and float needle. Still pouring fuel after about twenty minutes or less of riding. I'm stumped now... any suggestions? Your help is appreciated.

 

[Brassneck]

Vacuum petcock leaking perhaps?

 

[Drizzle]

I don't believe I have a vacuum petcock. Only one output on it that is for fuel. Wish I could take a picture but not near the bike. It's on a sportster tank. When I set it to ON position it pours fuel like it should. Carb is not restrictions flow like I thought it should

 

[Drizzle]

I don't believe I have a vacuum petcock. Only one output on it that is for fuel. Wish I could take a picture but not near the bike. It's on a sportster tank. When I set it to ON position it pours fuel like it should. Carb is not restricting flow like I thought it should

 

[fredintoon]

Hi Drizzle,
it don't matter if you have vacuum petcocks or not.
A vacuum petcock automatically shuts off the fuel when the engine stops.
It does nothing to stop a carb overflowing when the bike is running.
You for sure have a carb overflow problem.
Check once more if the needle & seat are OK, the float ain't sunk and the float level is where it should be.
The "usual suspect" will then be the float hanging up on the float bowl gasket.
Sometimes you gotta trim those gaskets with a razor blade to make sure they don't stick out to interfere with the float movement.

 

[Drizzle]

I will definitely check all that thank you. The float, seat and needle are all brand new so hopefully they are good but I bet your right about the float getting stuck. I planned on setting up a little station with the carbs over a bucket, bowls off, pour fuel into them and lifting the floats by hand to see if they shut off fuel. If everything works there then I will check clearance.