Elementary question - leaky carbs

[khittner1]

Chuey----It may be the float needles/seats as others have suggested, but there may be a more elementary cause for the leakage---are you sure that your leaking problem isn't from shot or misaligned float bowl gaskets? I've found that whenever I pull my float bowls off, there's about a 1 in 4 or 5 chance that I don't get the bowls and gaskets just right, with fuel leaking onto my toes (or a puddle under the affected side) being the first indicator. Fresh float bowl gaskets, fully tucked into their retaining grooves on bottom of the carb bodies, might be a problem-solver if you're lucky.

Konrad

[Jean]

Yeah, Khittner, MY last "leaking carb" problem was caused by an OLD gas line leaking at the cross-over tee. Worked on the carb 2 times and FINALLY saw the REAL problem and replaced the gas line!!.
Carb is REALLY clean, tho.
PS. I have also experienced the "flamin' boot"...

[jagarra]

Fired up my BMW this afternoon, do it every few days till the title gets sorted out and I can legally ride it on the street. Noticed a puddle of gas under the left carburetor, guess mine developed a sympathetic problem too. The only section of gas line not replaced is the portion going from the T to the bowl. At least I already have all the internals purchased to rebuild them. Was working OK last few months and now mysterious leak has suddenly appeared. Guess it may be time to just pull them both and go through the carburetors, as I can't ride it anyway.

[JACK ETHRIDGE]

Trash in the float neddle seat is most likley the cause of the leak. I would replace/check the neddle and then blow out the seat. Bings are bad about overflowing with trash in the seat. You could use a Q tip and brasso to polish the seat.

[Chuey]

I think it may be sinking floats. Here's how I came to that conclusion: I took the bowls off and if I hold the floats up, the carbs don't leak but if I let them drop, it runs out profusely. Does the fact that it doesn't leak if I hold them up mean the needles and seats are OK?

I have some of those airplane floats that people say don't do a thing. They are new (I bought them years ago, just a day before reading that they don't make any difference.) Should I put them in? Should I wait until Tuesday when the BMW dealer is open and buy new floats? Is there a way to test the floats?

Chuey

[Deleted User 72]

I think it may be sinking floats. Here's how I came to that conclusion: I took the bowls off and if I hold the floats up, the carbs don't leak but if I let them drop, it runs out profusely. Does the fact that it doesn't leak if I hold them up mean the needles and seats are OK?

I have some of those airplane floats that people say don't do a thing. They are new (I bought them years ago, just a day before reading that they don't make any difference.) Should I put them in? Should I wait until Tuesday when the BMW dealer is open and buy new floats? Is there a way to test the floats?

Chuey

Seems like I heard that the float should weigh 12 grams. But its been a while and I have an EZ Berg seat on my RS.

[JACK ETHRIDGE]

Holdinfg the float up with your had puts more presure on the needle than the float will so it may shut off the gas. The float needle is soft on the end and the trash could be sinking into the soft stuff. Put the float in a small bowel of water or gas and see if the float sinks or . Search the web for "Bing Carberator Floats" that may bring up Snow Bums site and he tells you way more thatn you want to know abouts carb float. You may want to get a new float and compair how the new and the old float and you will have spar if the old one is good.

[SteveD]

... Put the float in a small bowel of water or gas and see if the float sinks or . .

If the float sinks in the bowel, does that mean you're eating too much fibre or your foods too rich?

Sorry JACK...couldn't resist!

[JACK ETHRIDGE]

Steve, Rich food will do it every time.

[Chuey]

... Put the float in a small bowel of water or gas and see if the float sinks or . .

If the float sinks in the bowel, does that mean you're eating too much fibre or your foods too rich?

Sorry JACK...couldn't resist!

Depends if it is a bowel of water or a bowel of gas. Either way, it seems like uncomfortable advice!

Chuey