TOPIC:

Hi all, finally got the fuel supply to the carby bowls sorted as you might of seen in my other post, took her for another run today, warm day, coming home she ran out of fuel, put the tap on the prime position and she fired back up and I made it home. So it looks like the vacuum line I have run is too close to the tappet cover or the heat of the engine is making the line soft and I lose vacuum and it shuts off the fuel supply. So has anyone come up with an idea to run that vacuum line at a right angle out of the tap and away from sitting on the tappet cover ?, or maybe I should find some sort of reinforced vacuum line that won't go soft and close ?. I took some time to regulate the vacuum to stop the pulsing, sort of got it set up like the lines to carby balancing vacuum gauges, a restrictor in the line to even out the pulse at low revs, anyway looks like it's back to the drawing board unless someone has had the same experience and figured out a fix ??, cheers






vacuum line sits on tappet cover, BAD

In that rubber line you get thin wall that is used for windscreen washers and the heavy wall that is for vacuum and doesn't usually collapse with the heat. Have you got the heavy wall line the wall is as thick as the hole down the middle.

Nah just checked, it's thin useless rubber hose, no good for vacuum in a hot environment, say what is that silicon vacuum hose like ?? is it strong enough or should I go with the reinforced stuff ??
P.S. at least I know the tap don't leak when the engine is off (no vacuum = no fuel)

Funny .... when I asked for the "petcock" the bikeshop owner looked at me funny, he said why call it that, the Americans call it that, it's a fuel tap, I just said I like the word and it sounds "dirty", we had a laugh and left it at that

If they say its for vacuum then get it and if it doesn't work go back and insert it.
I would try to not let it touch the engine if possible.

RickG wrote: I would try to not let it touch the engine if possible.

Tough one mate, hose connection comes out of the tap facing the tappet cover, nothing a few cable ties might fix

I fitted one of these recently & had the same issues.

Even if you get the vac pipe sorted, I do not believe this tap can deliver enough fuel at mid to high revs for our 3 large float bowls.

I tried & tried, fitted all new seals & diaphram etc, but ended up just putting it down as a bad thing & fitting the original "leaky" type tap with a secondary inline tap as back up.

The concept of this tap is brilliant, but in practice its a nightmare !!

Best of luck & hope you have more success then me !!

Pete F
UK