Fuel Supply Problem

Tue Sep 07, 2004 6:37 am

Had a bit of a fuel leak on My Missey a week or so ago around the sediment bowl. Removed bowl, cleaned it out and found that it had a rubber washer and was leaking around the washer. In fact all the fuel in tank drained out. Replaced with the proper cork washer and now it holds fuel, however when cranked it will not fire. There is some fuel dripping from carb when I crank but no Smooth purring sound like before the leak and the tank drained. Never had trouble starting before. Ideas?

Fuel Supply Problem

Tue Sep 07, 2004 6:51 am

I have this same problem every time I let my Cub run out of fuel.
I think the float sticks and the fuel just runs through the carb.

I bet if you will pull the rubber hose off on the breather side of the carb it will be full of fuel.

Tap on the side of the carb, then add a little fuel to the gas tank.
If fuel doesn't start leaking out of the carb, the the float is working.

I have to go through this drill every time I let her run out of fuel.

Hope this will help.


Tue Sep 07, 2004 7:44 am

May also have stirred up a little dirt that has become lodged under the float valve.

Tue Sep 07, 2004 7:45 am

More than likely some debris has made it's way to the carb. Several places to check.
Check the screen at the input of the carb. There's a small screen inside that's hard to see.
Check the main jet, the small hole in the end tends to get plugged. Use a small piece of wire to clean it out being careful not modify the shape of the hole. These are things that can be done without taking the carb of the tractor.
If the problem persists, remove the carb and give it a total cleaning paying close attention to the needle valve. Remember what the old gas caps said :!: :!: :lol: :lol: :lol:

Tue Sep 07, 2004 10:13 am


If your float sticks when you let it run dry, the float is hanging up on the side of the fuel bowl. Either the float needs to be recentered or the bowl casting is distorted inward on one or more sides. Tapping on the carburetor to free the float bends the soft aluminum casting more. It's better to fix the bent casting than hit the carburetor to get your Cub running. Eventually your float will get a hole worn where it scrubs against the bowl.

Lurker Carl

Fuel Supply Problem

Tue Sep 07, 2004 12:33 pm

Hi Carl,

Thanks for the suggestion!!

I just discovered this thing with the float sticking a couple of weeks ago when I let her run out of fuel twice.

I was thinking that the carb needs to be rebuilt, so now might be a good time to do it.