fuel control valve

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alby 34

fuel control valve

Post by alby 34 »

I have an 1960 R69 that has a leaking control valve which is original to the bike. Where can I get a replacement or rebuild this one.
Allan Atherton

Re: fuel control valve

Post by Allan Atherton »

If the leak is external (gas dripping from the petcock), you may be able to stop the leak by tightening the petcock with a wrench to compress the red sealing gasket, or you may need a new gasket.

If the leak is through the petcock (it won't shut off), then it needs to be rebuilt with a black rubber internal gasket.

If the petcock has a metal face, with ON to the rear and OFF down, I think it is an Everbest and I think they are hard to rebuild and must be sent to a specialist. I don't think you can buy Everbest any more.

If the petcock has a black face, with ON down and OFF to the rear, I think it is a Karcoma and can be more easily taken apart and the interior rubber gasket replaced. You can also buy a new Karcoma petcock on the Huggett website.
Allan Atherton

Re: fuel control valve

Post by Allan Atherton »

Here are the instructions I followed when I rebuilt the petcock on my R100/7, which was the same as the petcocks on my R69US and my R27, which I think are called Karkoma:

I am assuming you have it off the bike, in your hand. To make the plastic outer ring slip off easier, drop it in a can or jar of very hot, but not boiling hot water. That will warm up the plastic & make it more pliable. Just slide one side off the rim of the petcock body, and the rest of the ring will just pop off. You may have to move the petcock handle one way or another to expedite, as I remember straight up & down don't work too well. The knurled ring unscrews with ordinary threads. It may be easy or it may be tough--carb cleaner & patience will loosen it. Use protection to avoid galling the outside of the ring, shop towels, etc. I use aircraft cannon plug pliers with nylon jaws, but that's just cause i've got them. Also, there is a large spring holding pressure on the handle to gasket connection, watch out for flying parts as the ring starts to come loose. Go slowly as you make the final disassembly, so you can see how the parts fit together. There are two metal shims that "bump" into each other to give your petcock the proper "feel" of on & off. One tab in one of the shims fits in that little slot you saw in the petcock body. This is a good time to clean out the gunk that has gathered in the area of the two fuel inlet straws up top. If you remove them make sure they go back in the same way, or you get a nasty surprise when you go to reserve! Replace the rubber disc & the O-ring. The smooth sealing surface that is the inside of the handle should be absolutely smooth for the repair to be successful. I use Simichrome polish. If the surface is pitted you should get another handle. Give the rubber bits a shot of silicone spray before reassembly. It is a bit of a bother to line everything up and hold pressure against the spring to reassemble. You may want an extra pair of hands, you can chuck it in a vise, or you can put the petcock body back on the tank temporarily. When you put your rebuilt petcock back on the tank, start tightening the threaded collar on the petcock & the tank at the same time, holding the petcock stationary. I use a new fiber gasket, as well as a small amount of Teflon tape.
Drew Daniels

Re: fuel control valve

Post by Drew Daniels »

Craig Vechorik of Bench Mark Works has posted a technical article on rebuilding the Everbest petcock. These are not ment to be rebuildable but I followed his directions and have been sucessfull. If you cannot find his site using a search engine contact me off this forum and I will send it to you.

Good luck,
Drew
Michael

petcocks

Post by Michael »

I need for a hoske tank petcocks size
12mm x 1.75 pitch male. also will have
2 hoske tanks for sale soon.
Michael
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