Vacuum tap - how to stop leaking?

[simesman]

Got the standard tap bolted to my '79 GS1000 tank and it weeps fuel slightly. It is not in need of a rebuild kit, it just seems to track down the threads of the mounting bolts. I can see the problem, you have seals that stop fuel leaking outside the mounting flange, but the slots where the 2x mounting bolts go are totally 'open' so that fuel dribbling down the threads can find it's way through the slots. I have tried loctite 572 as that claimed it was petrol resistant, but still get a slight weep.

Is there a standard fix for this?

[gs7_11]

You should have bonded washers on those screws to prevent leaks.

If it's all assembled correctly, there's no leak path.

[simesman]

Agreed, and using the bonded washers, but what stops fuel leaking down the threads and then outside the slots? The rubber part of the washer cannot seal against the slot. Maybe I have  a dodgy tap with slots rather than holes?

[gs7_11]

Yes, shouldn't have slots.

The washer should form a seal between the screw head and the body of the tap.

Sounds like you've got the wrong tap. Two types, 44mm and 50mm spacing, depending on year for the GS1000.

Get the right tap!

[simesman]

If there is a tap with holes rather than slots, then that is the one for me, thanks! Mine is 50mm spacing but it looks like my tap will fit both spacings. Wonder how anyone is supposed to seal a slotted tap!

[gs7_11]

You can't, that's the problem.

The reason why someone's done that to your tap is because the only 50mm taps are the stupid "on or prime, screwdriver only, no off position" ones that Suzuki went to for half a year.

The only other option is a Pingel.

If you can think of a tap that fits and has off and reserve positions, is be happy to hear it!