Elementary question - leaky carbs

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Chuey
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Joined: Mon Aug 02, 2010 11:56 pm

Re: Elementary question - leaky carbs

Post by Chuey »

Oh, I forgot to mention, it ran really nicely when I started it up. The only thing is it was leaking gas from the carbs.

Chuey
Darryl Flynn
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Location: Durham City, ENGLAND

Re: Elementary question - leaky carbs

Post by Darryl Flynn »

Sticky float needle. 100%

Darryl
My other bike is a Guzzi
ME 109
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Location: Albury, Australia

Re: Elementary question - leaky carbs

Post by ME 109 »

I've had a nice idle with fuel pissing out of one or both carbs.
How old did you say your needles were Chuey? As has been said, start with new needles to make an assessment.
It is indeed unlikely that the seats are the problem, unless someone like me has been in there. :?
My float pins are now removable either way, as they have been out that many times. :?
It doesn't really matter if the pins are loose because they can't come out when the bowl is in place. The bowl is about 2-3mm from each end of the pin. The best thing about a unidirectional pin is that there is no....er, what way does this thing go again... :roll:
The hair springs that hold the needle to the tang (if you have them) are a pita. The carbs will function perfectly without them.

Flamin' Boots.
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lrz
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Re: Elementary question - leaky carbs

Post by lrz »

Been roofing all day; here's that link:


http://www.bmwmoa.org/forum/showthread.php?t=60489



Pretty lo-tech.
Chuey
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Re: That link was a trip!

Post by Chuey »

I liked it when one of the comments said he was a "little leary". I guess you never know when someone will drop acid and decide to rebuild BMW carbs. Wow! It's like a whole universe in that float bowl! Those floats are so beautiful! Wow, man.

I'm pretty sure it's just some stuck needles. I'll dig into it tomorrow morning.

Chuey
Garnet
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Re: That link was a trip!

Post by Garnet »

Chuey wrote:I liked it when one of the comments said he was a "little leary". I guess you never know when someone will drop acid and decide to rebuild BMW carbs. Wow! It's like a whole universe in that float bowl! Those floats are so beautiful! Wow, man.

I'm pretty sure it's just some stuck needles. I'll dig into it tomorrow morning.

Chuey
After the effects of the wine, I hope. ;)
Garnet

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Garnet
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Location: Victoria BC Canada

Re: Elementary question - leaky carbs

Post by Garnet »

ME 109 wrote:I've had a nice idle with fuel pissing out of one or both carbs.


Flamin' Boots.
I just dug my winter /5 out of mothballs and am not allowed to leave my boots (left one) in the front hall closet. :oops:

Maybe I'll fix it tomorrow with Chuey. But it's supposed to be sunny................. :? :?
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ME 109
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Re: That link was a trip!

Post by ME 109 »

Chuey wrote:I'm pretty sure it's just some stuck needles. I'll dig into it tomorrow morning.

Chuey
'Course there's always the possibility that some crud from the tank or a bit of fuel line has got itself stuck in the seat where the needle contacts. I've had that before.
Sometimes allowing the float to drop all the way down and turning on the fuel will flush it out.
Otherwise disconnect the fuel line where it enters the carb and give it a shot of compressed air where the needle goes.
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George Ryals
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Re: Elementary question - leaky carbs

Post by George Ryals »

The float level could be too high and the leak is the overflow. or the float could be sinking, causing a high level in the bowl to be too high.
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khittner1
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Re: Elementary question - leaky carbs

Post by 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
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