Is the vacuum fuel tap faulty..

[ray 316]

l have a fuel problem and could do with a bit of help and advice. l have a 50cc moped and the overflow pipe on the carburettor is seeping fuel even when it's not running. l have cleaned out the carb and fitted a new float valve but it's still seeping fuel.
The moped has a vacuum fuel tap fitted under the tank and the top hose goes to the carburettor and the vacuum hose from the inlet side goes to the vacuum fuel tap bottom.
l have the carb off at the moment with the rubber hose for the fuel to carb from the vacuum tap clamped , but as soon as l release the clamp fuel just keeps coming out even when l suck on the vacuum pipe it makes no difference.
l thought fuel did not come out the fuel side till there was a vacuum, so is the vacuum tap faulty.
Could this be the cause of my carburettor seeping fuel out the overflow pipe because of constant pressure of fuel on the float valve causing it not to shut off properly.

[Kickstart]

Hi

Vacuum fuel tap works by allowing fuel to pass when there is a vacuum (ie, it should flow when you suck on the vacuum hose).

However it should be fine and not flood if the needle valve is clean and unworn, and the float height is set correctly.

If more fuel gets into the float bowl passed the needle then it will lift the float harder and close the needle valve even tighter.

All the best

Keith
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