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By klutz
#3352
I have noticed fuel slowly dripping from a small brass spigot on the bottom of the floatchamber of the VM-28 Mikcarb carburettor on my 2004 500 Bullet. Can anyone suggest what might be causing this ?
Many thanks.
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By PeteF
#33890
Could be the float needle not sealing or the float level.
There are useful tech notes here on Mikarbs.
By klutz
#33891
Thanks Pete, I will take the float chamber off tomorrow and check it's all working. This spigot doesn't seem to appear on any of the diagrams in the manual or online which adds to the confusion.
By Nettshubby
#34016
This is the overflow pipe, and is usually having a plastic drain tube connected. If fuel is coming out it means the float chamber is flooding, probably due to either a sticking float pivot, or float/feed valve having muck on it and not shutting off fuel when at correct level.

If you remove the bowl you will see a tube sticking up inside, this is the overflow level tube, when fuel reaches this it drains through the "stub" you mention.

Ray.
By klutz
#34084
Many thanks Gents, it was indeed dirt in the needle valve. Now sorted.
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By PeteF
#34087
Not a bad idea to stick ASN in line filter in the feed.
By Nettshubby
#34088
When I said the tube inside the float bowl was the overflow i beleive it is actually the fuel feed for the cold start circuit.

Sorry, another senior moment!

Ray.

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