RV-3 Fuel Valve

I have a 92 RV-3, and when I switch tanks with the fuel valve, the fuel valve leaks a little bit of fuel onto my fingers. I tried to search through the forums for a fix. It is a older 3 port valve. I found a similar valve on Aircraft Spruce called the homebuilders or weatherhead shutoff valves. On the Van's site, it says Replacement of the older 3 port valve (used on early RV-3/4/6 - no longer available) will require modifying fuel lines.

Mine is a 180 degree turn selector. It doesn't stick, just leak. Has anyone dealt with this? Anyone have a suggestion to fix this?

Thanks!

Derek

If you don't need it right away, I think I have a new unused RV-3B valve that came with my kit. I'll be using the aftermarket Andair valve instead.

Send me an email or PM if you're interested (click on my name in the upper left to get that menu) - the valve must be at the hangar or in one of my parts bins down at the bottom somewhere.

Dave

Before you go to the trouble of replacing the valve, you might try servicing the one you have - very likely all it needs are a couple of O-rings. The valve stem comes out the front, very easy to do. At worst, you have to drain the tanks before working it, but you can do that by flying!

Paul

Ironflight said:

Before you go to the trouble of replacing the valve, you might try servicing the one you have - very likely all it needs are a couple of O-rings. The valve stem comes out the front, very easy to do. At worst, you have to drain the tanks before working it, but you can do that by flying!

Paul

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If I replace the o-rings, is there anything special about them or do I just buy a o-ring assortment from harbor freight and see what fits?

Derek343 said:

If I replace the o-rings, is there anything special about them or do I just buy a o-ring assortment from harbor freight and see what fits?

Click to expand...

My guess is that these tractor valves are built with whatever generic o-rings they have on hand at the time....but I think you might find Vito in the correct sizes as well. Some one will probably come along and give the sizes or part numbers....

Derek343 said:

If I replace the o-rings, is there anything special about them or do I just buy a o-ring assortment from harbor freight and see what fits?

Click to expand...

I would at least purchase them from ACE hardware or NAPA autoparts.

The valve has one under the cap and one around the shaft. Unscrew the cap and pull out the selector. Back off the screw then tap the screw head with the handle of the screwdriver to remove the handle. Both O rings fit in the cap.

With the fuel level below the fuel valve, this is a 10 minute job.

There are "O"rings in that seal the stem from fuel leaking past it. I had the valve in the Cub leaking at OSH one year and replaced it with the Teflon cord used for sealing faucets I found Ace Hardware (or somewhere) as a temporary fix; FAA/PMA approved, of course. Worked fine stopping the leak except the valve was harder to turn. Take the valve apart (remembering the order and orientation of things; take pictures if you have to) and go to your local hardware store or tractor supply (where I got mine), taking said "O" rings with you to match up with what they have there. I got several sizes that were close to the original and a few spares for later. Good hardware stores will have multiple bins of different sizes and may be of better material than Harbor Freight. While it is apart, if you can find someone with fuel valve lubricant which is a special type of lubricant that does not dissolve with contact with fuel, get some and apply a THIN coating on the plunger itself. Whether it is brass or nylon it will turn easier. I have a film can (remember film cans??) that was initially full of lubricant that I have had for 30 years and have used about 25% of what I originally had. Do NOT use other greases as they will be washed away by the fuel. Do NOT overuse the valve lubricant or you will find it in your gascolator screen or fuel filter....

If all else fails I’ve a RV6 valve 1999 vintage, new, you can have for shipping cost. PM me if desired. Pictures on request. Marty

Make sure they are made of Viton, not Buna. Viton is rated for gasoline. Your average o ring assortment is going to be buna.

Derek343 said:

If I replace the o-rings, is there anything special about them or do I just buy a o-ring assortment from harbor freight and see what fits?

Click to expand...