Fuel vacuum tap. By minarelli (Read 955 times)

[minarelli]

Hey guy's just come across this on a bike i brought about a month ago. I've noticed someone has blocked up the bottom line on the vacuum tap with a bolt connected to some fuel line? i removed the bolt from the bottom line and it shoot's out fuel (engine not running) but if i take the line that runs to the carb that flows fuel aswel.Does this mean my vacumm fuel tap is broken here is a picture of the fuel tap.

www.ebay.co.uk/itm/CHINESE-4-STROKE-SCOOTER-VACUUM-FUEL-TAP-YIBEN-JINLUN-PULSE-BAOTIAN-ZHEN-/251272552325?pt=UK_Motorcycle_Parts&hash=item3a8102df85

[FACE PLANT FOR LIFE]

Sounds like the diaphragm on the fuel cock/petcock/vacuum tap is broken. Replace it and it should stop leaking like that. If your carb ever fails and stops sealing the gas in, you'll have gas everywhere + a flooded engine.

[Bashan]

The bottom nipple is vacuum and the upper one is fuel. Fuel is not supposed to flow until there is a vacuum applied to the diaphragm from the intake manifold. Amulet is correct, the diaphragm is probably torn and it is allowing fuel to pour past the diaphragm into both nipples (is it warm in here?). I would plug the vac line at the manifold, put a brass fitting into the tank, and use a Briggs & Stratton manual valve. Then you don't have to deal with that vacuum crap. Rich

[masterburt]

Thanks guys,I have been told i have OCD because i cant leave something that's been messed with.much appreciated for all your help.. thanks

[rks]

You can probably blame our ethanol laced gasoline for your failed diaphragm, good reason to seek out and use non ethanol gas, if available where you are.