fuel selector valve

[paul zerkel]

I has suspected I had a gas leak. I confirmed that today, and discovered it appeared to be coming from the fuel selector valve. What is the failure
mode of these. After I started the coach and ran it from the main tank for a few minutes, gas kept dripping out at the valve.

I was not sure if it was the valve itself or the hoses going into it. A few years ago I replace all the rubber hose from the selector valve to the
fuel pump with Gates Barricade, and all that appears to still be in good shape. The leak in my case appeared to be coming from the top connector input
into the selector valve. Which is plumbed to the main (rear) tank.

What surprised me was when I took that hose off the top input connector, gas kept coming and coming from that port on the input to the selector valve.
What I did as a quick fix what put a short plugged fuel hose onto that input. But of course then I could only draw fuel from the aux tank.

My question: is this normal behavior of the fuel selector valve when one input hose is disconnected, or does it mean I likely have a defective
selector valve.

I inspected the hose I pulled off the input and it was pretty chewed up. But I am not sure if it just had deteriorated or I tore it up trying to get
it off. Probably some of both. Ultimately I cut it back about 12 inches and got a hose barb connector and patched a new piece of Barricade in its
place. That appears to have stopped the leak for now. But I know the real long term fix is to drop the tanks and replace the fuel hoses from the
senders to the valve.

Again my main question is: Is this leaking from the disconnect input normal behavior of the fuel selector valve when one input hose is disconnected,
or does it mean I likely have a defective selector valve?

Thank You.
--
Paul Zerkel
'78 Eleganza II
Salisbury IL (near Springfield)

 

[Ken B]

Here is the problem. If you disconnect the main tank hose at the valve with the power off, the valve is set to main tank. The hose is full of
gasoline from the engine driven fuel pump all the way back to the tank. You are probably just seeing that stored gasoline draining out.

As far as leaking when running you probably have a bad connection at the valve pump or a cracked valve. There should be no pressure at the valve
because it is on the input (suction) side of the fuel pump. If you have installed an electric pump then the pressure situation changes depending on
where you mounted and plumbed the pump.
--
Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana

 

[jim kanomata1]

If the selector valve is older than 4-5 years, replaceitas the rubber
inside is deteriating from ethanal.

> Here is the problem. If you disconnect the main tank hose at the valve
> with the power off, the valve is set to main tank. The hose is full of
> gasoline from the engine driven fuel pump all the way back to the tank.
> You are probably just seeing that stored gasoline draining out.
>
> As far as leaking when running you probably have a bad connection at the
> valve pump or a cracked valve. There should be no pressure at the valve
> because it is on the input (suction) side of the fuel pump. If you have
> installed an electric pump then the pressure situation changes depending on
> where you mounted and plumbed the pump.
> --
> Ken Burton - N9KB
> 76 Palm Beach
> Hebron, Indiana
>
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--
Jim Kanomata
Applied/GMC, Newark,CA
jimk
http://www.appliedgmc.com
1-800-752-7502

 

[johnny]

What JimK said. Here's one solution:

http://www.gmcmhphotos.com/photos/g6198-cane-9-creek-rv-park-heflin-2c-al.html

That's a pair of Mr. Gasket pumps, the relay is driven by the tank switch instead of the valve which isn't used in this configuration. Mr. Gasket
pumps have check valves at their output so none are needed. The supplied filter for them is junk and will leak, replace it with the Wix identical
filter at install. Works fine, lasts a long time.

--johnny
--
76 26' Eleganza(?) with beaucoup mods and add - ons.
Braselton, Ga.
"I forgive them all, save those who hurt the dogs. They must answer to me in hell" - ol Andy, paraphrased