Fuel Leak

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mcferreira100
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Fuel Leak

Post by mcferreira100 »

So after a carb clean it was running ok for awhile. Now got a bad leak in first carb from the fuel tap. Was told to drain carb with bike running which cured it that day. But 2 days later its leaking again. So can I take it float valve probably sticking. Any fixes without getting carbs off again??

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Re: Fuel Leak

Post by Larry Zimmer »

Can you determine where the leak is? Is it between the carbs coming from the fuel junction between carbs #1 and #2? (Hope not!) If so, it would seem to be the oring(s). That would require removal and separation!!!!! :evil: If it is coming from the overflow tube, then, could be sticky float. First thing to try there is a sharp rap or two against the float bowl with the blunt end of a screwdriver. This for a start. Good luck.
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mcferreira100
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Re: Fuel Leak

Post by mcferreira100 »

Difficult to see..dripping big time what seems out the inside bowl screws. Been reading up and see it could come from seals between carbs..can`t be sure unless tank comes off. Strange if the carb is drained it stops and can ride all day no problem.

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Re: Fuel Leak

Post by steve murdoch icoa #5322 »

Certainly with the carbs on the bike there is enough room on #1 carb to access the float, needle and filter. Give 'em a clean.
While you have the bowl off you can also check the float height

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Jeff Bennetts
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Re: Fuel Leak

Post by Jeff Bennetts »

mcferreira100 wrote:So after a carb clean it was running ok for awhile. Now got a bad leak in first carb from the fuel tap. Was told to drain carb with bike running which cured it that day. But 2 days later its leaking again. So can I take it float valve probably sticking. Any fixes without getting carbs off again??
If your float valve is sticking or has a small piece debris keeping it open, try starting the bike and tap on the lower body of the carb with a plastic or hard rubber mallet, don't get carried away just tap the bowl and body of the carb from all angles you can reach.

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Re: Fuel Leak

Post by EMS »

The float seats are finicky. I did the carbs on my CB1100R last year and took them off 3 times, because they kept leaking through the overflow. Only after I thoroughly cleaned - almost polished - the float seats, they were O.K.

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Re: Fuel Leak

Post by Larry Zimmer »

War stories with carburetors: Rebuilt the carb of a '67 Ford years ago. Float hung on it through 3 rebuilds. After the third hang-up, 'adjusted it' with a tire iron. Never had a problem for the next 100,000 miles when I sold it. Just sayin'...........
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Re: Fuel Leak

Post by Mouse »

Larry Zimmer wrote:War stories with carburetors: Rebuilt the carb of a '67 Ford years ago. Float hung on it through 3 rebuilds. After the third hang-up, 'adjusted it' with a tire iron. Never had a problem for the next 100,000 miles when I sold it. Just sayin'...........
:lol:
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EMS
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Re: Fuel Leak

Post by EMS »

You also need to really check where the leak is, as Larry said in his earlier response. If it is just a matter of the float needle seat leaking and overflowing, the fuel should come out of the overflow tubes on the bottom of the bike - if you still have them. A leak between the carbs is not only or not at all a float valve seat issue.

mcferreira100
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Re: Fuel Leak

Post by mcferreira100 »

I heard if float valve sticking, the bowl will overfill and flood the cylinder which will make the bike run pretty lousy. The bike seems to run fine so does this not indicate leak is more likely between carbs?, specially as it is really pouring out..and not out the carb overflow.

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Re: Fuel Leak

Post by Larry Zimmer »

"Unfortunately' all things point to the joint between the carbs. Unfortunately, because the only fix is to pull and separate the carbs to install new orings. Be certain to use Viton material orings. They are much more robust than nitrile rings. (OEM type from those days).
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