IP2 petrol tap

[gripper]

the latest snag is a petrol tap stuck on. I could see some fuel leaking from the cross frame link pipe and thought it would be a simple job to replace that pipe. Wrong, remove pipe and flood the floor. I would expect the tap to fail to open but stick open? Hmm. could be an ethanol issue. Without taking it apart yet, it looks like a Suzuki item from a late 70s GS850 or similar. Any advances on that? Throttle still sticking open at about 85, good job my hair is already grey.

[Richard Negus]

Dave,It's possible a tap repair kit may fix it, but I've had one recently where the valve seat had corroded so badly that the kit didn't fix it and I needed a new tap.That particular tap was specified by Norton in about 1978, but I've no idea which bike it was originally fitted to.Mikuni were fairly conservative on flange shapes, so if it looks right on E bay, it will probably fit the tank.The repair kits are available from a distributor in Manchester Victoria, or were.If you're feeling flush, ANIL have new taps.

[gripper]

Thanks for that Richard. The pictures on ebay show a tank to tap gasket with a thick and thin cross bar. The rest of the bits look similar to a Suzuki GS850 so I'll wait and see what my £16.80 gets me. The inside of the tap looks ok. Reassembling it with the original diaphragm, it seems to work and close under it's own steam/spring pressure. While I've gone to the trouble of draining the tank etc I'll fit a new kit and soda blast the tap body. (first)

[gripper]

Well the suzuki kit fitted and the seat in the tap body is gleaming but the tap dribbles a bit of fuel when it should be off. I've stretched the spring to encourage the valve to seat a little more positively. Wether it will take a little time to bed in remains to be seen but until then, hopefully, my viton tipped float needles will have to do the biz.

[gripper]

Given up on the vacuum operated tap. garage stinks of fuel. going to fit a manual in line tap that has an OFF position. One less thing to go wrong.

[gripper]

I had another go at the tap but it was still leaking. Finally I replaced the original diaphragm and the thing is working again as advertised. It would seem that the replacement diaphragm and spigot are not long enough to bed onto the seat properly, probably only by about 0.010" Studying the tap closely there is a curved port in the face of the tap lever that appears to do nothing. If I were to turn up a new lever/valve and eliminate this port, I reckon I could give myself an off/ on/ res position but I would have to plate over the diaphragm housing. One of those jobs that you probably never get round to doing.