Question on gas tank selector valve.

[firefighter]

Hi guys,

I have a 1976 3/4 ton 4x4 and it has the dual gas tanks.
My fuel tank selector valve has one electrical wire and 6 hoses going to it and then it has one other port that appears to be purposely left open. Is this a vent of some sort?
Well last summer it had started seeping just a bit so I just slid a rubber cap on it and it seemed to quit. Well now that the cab is back on and it's much harder to get to, it has started dripping a drip every now and then while my truck is just sitting there.
Can I just get a clamp & hose and permanently cap it off, or is this an issue that needs to be addressed?

My gas tank senders have 3 outlets on them. One is a vent for sure, one is a supply and the other one must be a return?
If I have to change the valve, do I have to stay with the 6 port valve or can I use the 3 port?

Thanks for any assistance you can give me.

[beastie_3]

Im not sure what the 7th port is for. You should be able to find some instructions that might tell you from Pollak, who is the company who makes the selector. Someone on here will probably chime in too.

[Project86]

Just went out and looked at mine, it does appear to be a vent, mine has a piece of hose on it to get out past the shield but I have never noticed any fuel leaking from it.

[bd]

...If I have to change the valve, do I have to stay with the 6 port valve or can I use the 3 port?

Stay with the 6-port, so your return line will dump into the same tank from which you're pumping fuel.  Otherwise, you'll end up transferring fuel between tanks and overflowing a tank.   

[bake74]

...If I have to change the valve, do I have to stay with the 6 port valve or can I use the 3 port?

Stay with the 6-port, so your return line will dump into the same tank from which you're pumping fuel.  Otherwise, you'll end up transferring fuel between tanks and overflowing a tank.   

      x2:  And by the way that sucks.

[firefighter]

Thanks very much for the replies guys.

I would stay with the 6 port one (and buy a new one) but can someone tell me if your 6 port valve has just a single electrical wire going to it? Mine only has a single electrical wire going to it and I thought I'd read somewhere that most 6 port valves have more wires going to them.

On a side note, I will say my engine mounted manual fuel pump does not have the return port on it so I have the return line (mounted on the frame next to the fuel pump) going back to the tanks plugged off.

Thanks again for the help !!

[bd]

The fuel return line from the 454 helped prevent vapor locking.  Not running it might cause stalling/drivability issues in warmer weather....

[firefighter]

The fuel return line from the 454 helped prevent vapor locking.  Not running it might cause stalling/drivability issues in warmer weather....

You know, while the front end is still apart, it would be way easy to replace this 15 year old fuel pump with one that has the return port on the pump. Then I can correctly hook up the return line.

Now, if someone could verify that their 6 port selector valve has only one wire, I'd be set.

Thanks guys!!

[firefighter]

I just talked to my local CarQuest guy and have the correct fuel pump ready to pick up.
I had him look at the gas tank selector valves too and the only 6 port one he has listed has a flat electrical connector set up for multiple wires.
That's what I was afraid of......
My 6 port selector valve only has one electrical wire and it appears factory.

[firefighter]

Ok, even though I'm at work, I've been sneaking in a little internet time.      Shhhhhh, don't tell the boss!!

I found the tank selector valve I have in my truck. It's an AC Delco tank selector valve part #467513.
It must not be an original and somebody in years past must have changed it. I've found the same valve on the internet and I think I'll just order a new one since my new hoses are already cut and installed to fit this valve.
I think I have my problem resolved.

Thank you to those that have replied, helping me figure this out.

[bake74]

     Did you ever find out if it requires more than 1 wire ?

[firefighter]

     Did you ever find out if it requires more than 1 wire ?

Yes sir. It only takes one wire.
I think I'm going to order it today.

[bake74]

     Good to know, and glad you figured it out.  (now I know for my 77 when I get around to it)

[firefighter]

New valve arrived today. $59 shipped through Amazon.com. Great price !!

Valve is installed. Was easier than I thought it was going to be. Only took 50 minutes.

Gas leak is gone and all is well.

Thank you all for your replies while I tried to figure this out.

[LTZ C20]

Just a thought Firefighter, your tank selector switch acts like a normal light switch. When you have the switch on the ride side, it sends current to the switching valve and opens the doors to allow fuel to pass from the corresponding tank. When you switch to the other side tank, the circut is imcomplete and the doors return to their other position, allowing fuel from the opposite tank. Now your sitch in the dash has multible electrodes, this is because when you switch to a tank, power is either sent or broken to the switching valve. When you switch tanks, power is sent to the corresponding sending unit in the respective tank. According to GM, the RIGHT side is your PRIMARY tank and the LEFT side is your AUXILIARY tank. this means that when on the right side, power is going to the switching valve, when on the left side, power is broken and the valve moves to the left side. Hope this helps.