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fuel tap issues
Posted: Tue Feb 28, 2012 7:39 am
by streetfighter
Hi there guys, me again, i got new float needles in, and set the level at 19mm, seem to be fine but fuel tap is constantly flowing.I have replaced the internals with a new kit, but the diaphram mechanism doesnt shut the fuel off.I was thinking of re-facing the surface that comes into contact with the o-ring plunger on the inside of the tap.Can anyone advise on this? Having endless trouble with this stink wheel!
Posted: Tue Feb 28, 2012 10:08 am
by martin
it should only constantly flow when it is in the prime position,running it on
on or reserve, would then work on the vacum, so would stop that.
but to be honest,it does,nt matter if the fuel tap is permanantly flowing as
the carbs will only use the right amount of petrol anyway
[double check you have the float heights correct]
and also make sure your shut off valves in the carbs are working
correct and not worn!
Posted: Tue Feb 28, 2012 8:40 pm
by john-b
I had a similar problem but it was because the spring inside the tap behind the diaphram was naff and so the oring didnt seat properly.
As martin says it shouldnt make any difference to the carbs overflowing though its just annoying when you take off the tank and get fuel all over you

Posted: Tue Feb 28, 2012 10:58 pm
by Howie
Have a look inside your tank fella,
Any sign of rust then you're asking a lot of your float valves. As Martin says, it doesn't matter which position your tap is in, the float valves will shut off the fuel at the correct level.
Check not only the float valve itself but also its seating, the damage may already be done.
And as a last 'wayout' suggestion, check the floats on the carbs themselves. They can split apparently, (never happened to me but hey)
Take 'em out give them a shake.
Hope this helps matey
Posted: Thu Mar 01, 2012 12:25 am
by fred
ive had it when the float valve doesnt seat ,just give the carb a tap,or a good shake,iv`e had this 4 times for no reason ,ime gona test this on my rebuild ,do the first prime n start on the paddock stands not on side stand