The left Bing carb on my R90/6 drips gas...aboout a drop a minute. I have replaced the float bowl gasket twice now but that has not helped. Could this be related to bad floats? I assume if the floats are bad then gas would continue to flow as long as the pet cock was open and the bowl would overflow above the height the gasket, soaking the cork gasket and causing it to leak. When I remove the bowl, open the pet cock and lift the floats the flow stops, which leads me to think my floats don't float, if you know what I mean. Any ideas?
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Leaking Bing Carb ...bad floats?
- Thread starter rbryson
- Start date
Check the float needle. Crud can get stuck in there and cause the float needle to NOT seat properly causing gas to constantly flow into the float bowl. You might have worn float needles depending on the age/mileage of the bike. This also results in the float needle allowing fuel to pass into the float bowl unabated.
Woodgrain
Woodgrain
O
OscarMayer
Guest
If the flow stops as you lift the bowls up to the carb then the diaphram is floating as it should.
Maybe there isn't enough pressure on the bowl as it is being held to the bottom of the carb.
You could try silicone gaskets. One company that makes 'em is called real gaskets.
g'luck.
Maybe there isn't enough pressure on the bowl as it is being held to the bottom of the carb.
You could try silicone gaskets. One company that makes 'em is called real gaskets.
g'luck.
J
James.A
Guest
The tiny brass tube that sticks up from the bottom of the float bowl is the overflow tube. A properly functioning and adjusted float/needle set should never drip. A worn or gunked up float needle can allow a carb to drip along with a sunk float. I had a sunk float on one of my 750's. It had turned black, where as the other one was varnish brown. If you find crud in the bottom of a float bowl, it most likely got there by going past the needle/seat, and some of it may have accumulated on the passage. Find the ad for Bing Agency in your Owners News and order the carb book. The best $10 you'll ever spend.
A simple test for floatability is to put the float in a small container of gas. About 1/3 of the float should be above the fuel line. Be careful when removing the float. The hinge pin has a knurled edge on one end...IIRC, you should lightly push out the pin starting on the knurled end. Don't apply enough force that you'll damage the posts that hold the hinge pin.
Also check to be sure there are no restrictions in how the float moves up and down on the hinge...it shouldn't bind at all.
Kurt in S.A.
Also check to be sure there are no restrictions in how the float moves up and down on the hinge...it shouldn't bind at all.
Kurt in S.A.
Had the same problem last year....called bing....replaced floats,neadles,and gaskets....use the cork gaskets....no more leaks. The cork gaskets expand when wet....a good thing,to stop leaks.They will leak a little when dry.....no gas in carbs.
My bike is over 30 years old ,didn`t test floats because I figured they were due a rest, and didn`t like gas in my shoes. Also found some of my leak was oil dripping from valve cover, replaced that too.Have heard of gas leaking from old fuel lines and dripping down carbs.
My bike is over 30 years old ,didn`t test floats because I figured they were due a rest, and didn`t like gas in my shoes. Also found some of my leak was oil dripping from valve cover, replaced that too.Have heard of gas leaking from old fuel lines and dripping down carbs.
6659
New member
By the way, I just put gas in a bike that hasn't run in over 20 years. I thought I would just turn on the gas and start the bike. Unfortunately, I turned on the gas and it started leaking everywhere. I turned off the petcocks and the gas just kept on pouring out. After the gas was completely drained, I opened the petcock up to find the cork valve inside was totally shrunken. Never thought about checking that before putting gas in the tank.
KHEEREMA129911
New member
All good points...but make sure you check that the metal bowl itself isn't leaking. I had a leak where the overflow tube (think that is what it is) is pressed into the bottom of the metal bowl. You could not see it with the naked eye, but I diagnosed it by taking the bowl off, wiping it clean, and leave some gas inside the bowl. Set it aside. If you note gas on the bottom some time later, it is somehow leaking through the metal bowl. (No matter how much you adjust the float, it will not correct this problem. Trust me.)
I am cheap, (or I have a big mortgage and too many toys) so I just used some JB Weld around the overflow tube inside the bowl rather than buying a new bowl. It stopped leaking, but I'm not sure if JB weld can withstand gasoline. I should probably check. The best way would probably be to replace the bowl.
I also noticed that turning your petcocks off when parked, and also parking on the centerstand will help reduce a leak if not eliminate it entirely.
I am cheap, (or I have a big mortgage and too many toys) so I just used some JB Weld around the overflow tube inside the bowl rather than buying a new bowl. It stopped leaking, but I'm not sure if JB weld can withstand gasoline. I should probably check. The best way would probably be to replace the bowl.
I also noticed that turning your petcocks off when parked, and also parking on the centerstand will help reduce a leak if not eliminate it entirely.
