carbs leaking.......advice please

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chrispyduck
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carbs leaking.......advice please

Post by chrispyduck »

Hi All

Hope someone can help.........

My otherwise perfect running bike has started leaking a lot of fuel from carbs 1 and 2 following a lay up of around 3 months.

I had previously drained the carbs in readiness for this period.........so today i put fresh fuel in the tank, turned on the tap and started her. The good news is she is firing beautifully on all 6 cylinders but fuel is flowing heavily from the float bowls 1 and 2. When the tap is off fuel doesn't leak. I have gone through the draining process again and stopped and started the fuel with no difference.
Any ideas please :handgestures-fingerscrossed:

Thanks in advance

Chris

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Jeff Bennetts
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Re: carbs leaking.......advice please

Post by Jeff Bennetts »

Tap the bowls with a small plastic or hard rubber mallet, lightly a couple times, you're just trying to unseat a stuck float, so tap the bowl where it seats with the carb body anywhere you can reach.

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Re: carbs leaking.......advice please

Post by chrispyduck »

Jeff Bennetts wrote:Tap the bowls with a small plastic or hard rubber mallet, lightly a couple times, you're just trying to unseat a stuck float, so tap the bowl where it seats with the carb body anywhere you can reach.
Thanks Jeff looks like No1 carb has stopped leaking with a few taps. Trying to reach No2 slightly more tricky :handgestures-fingerscrossed:

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Re: carbs leaking.......advice please

Post by Jeff Bennetts »

chrispyduck wrote:
Jeff Bennetts wrote:Tap the bowls with a small plastic or hard rubber mallet, lightly a couple times, you're just trying to unseat a stuck float, so tap the bowl where it seats with the carb body anywhere you can reach.
Thanks Jeff looks like No1 carb has stopped leaking with a few taps. Trying to reach No2 slightly more tricky :handgestures-fingerscrossed:
Use the handle of another hammer or wood handle of a similar tool or just a 1x1 piece of wood long enough to reach the inner carbs, use it as a drift and deliver a few taps to the carb bowl/body.

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Re: carbs leaking.......advice please

Post by EMS »

I had breathing issues for a while. I regularly used an inhaler - until I found the right pulmonary specialist. He addressed the root cause of the problem rather than me continuing working on the symptoms.....

Take the carbs off and clean them. Make sure you address the float valve seats. 8) 8)

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Re: carbs leaking.......advice please

Post by daves79x »

If you get the carbs to stop leaking, you can at least ride it, but I'm with Mike - I wouldn't trust it at all, especially since one of the leakers is #1. You are asking for a hydrolock. You can replace the float valves on #1 and 2 without removing the carbs. Take the alternator off and you can get to them.

Dave

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Re: carbs leaking.......advice please

Post by Jeff Bennetts »

Might be the best advice you ever receive here, at least do what Dave suggests, you can see the general condition of the carbs by pulling the two outer carb bowls and removing the float, needle and seat. Inspect everything for wear or debris or a cracked overflow tube in the bowl.

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Re: carbs leaking.......advice please

Post by Larry Zimmer »

ALSO -- do some 'hard' looking to see if the fuel is actually leaking from BETWEEN #1 and #2. That would be leaking o-ring seals at the fuel transfer tube between the carbs. This leak will, naturally, accumulate on the bottom of the float bowls; and, thus, appear to be leaking floats. Leaking float valve should show, typically, at the end of the drain tubes; not on the bottom of the float bowls.

This would need disassembly and replace the orings for all the carb transfer tubes. Often, the first few occurrences will find that the leak will stop after a short time with fuel. However, it will eventually not stop. Old 'rubber' tends to loose its plasticizer after 30 or 40 years. Especially in volatile stuff such as gasoline. When you do replace the orings, be CERTAIN to use orings of Viton material.

(signed) Been there; done that
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Re: carbs leaking.......advice please

Post by daves79x »

Larry is, of course absolutely correct. I’m assuming though, that your leak is for sure coming out the bowl drains. If not, then they MUST come off.

Dave

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Re: carbs leaking.......advice please

Post by chrispyduck »

Thanks for all the support and advice.

I can confirm after a few taps and left standing for 24 hours the leak stopped and the bike is running fine. Carb No1 actually stopped leaking shortly after my initial post followed by No 2 the following day.........the floats had stuck in the down position.
I appreciate the advice regarding inspection of these 2 carbs and will take a look however i am comforted by the fact the carbs where overhauled by the previous owner (who was a senior executive of Honda UK) with seals and floats being replaced.

Regarding hydrolock i always turn off the fuel tap to prevent fuel leaking.

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