Faulty rigged

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jonbgood

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east bay area , California
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Johnny
Truck Year
1977
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c20
Engine Size
454
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Just picked up this 77 c25. It smells of heavy gas fumes. I got under started looking around. Apparently they removed all the cross over hard lines to dual tanks and ran all rubber hoses. The original switch valve has been removed and replaced with two small pumps for sending and return. They also cut the plug for original switch and must of removed wire because I don’t even see 5wires to reinstall plug if i wanted to. Some of the hoses leak a bit out of ends where meet hard lines running to front. Please I need advice on how should I move forward. Should I remove tanks and only put one back or what would you do to get it properly set up?
Thanks for all advice
 

waterpirate

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Welcome!
Stop, breathe, think.
The mess you have needs to be fixed, safety issue. The question is what are your plans for the truck? If a working driver, make it safe and go to work. If you are planning a restoration, then restore to original.
Eric
 

Strick

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Dad's ole C20 Crew has a selector valve with one wire like the one in the pic. It appears that your truck has two installed for some odd reason.
 

bucket

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Dad's ole C20 Crew has a selector valve with one wire like the one in the pic. It appears that your truck has two installed for some odd reason.

Yeah, it looks like the truck had a 6-port valve and they couldn't find one, so they used a pair of 3-port valves. I don't see why that wouldn't work.

However, I do see a glass fuel filter that absolutely has to go. If it's not leaking currently, it will be.
 

jonbgood

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east bay area , California
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Johnny
Truck Year
1977
Truck Model
c20
Engine Size
454
Welcome!
Stop, breathe, think.
The mess you have needs to be fixed, safety issue. The question is what are your plans for the truck? If a working driver, make it safe and go to work. If you are planning a restoration, then restore to original.
Eric
I’m going to use it as a work and daily short distance driver.
 

jonbgood

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1977
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c20
Engine Size
454
Yeah, it looks like the truck had a 6-port valve and they couldn't find one, so they used a pair of 3-port valves. I don't see why that wouldn't work.

However, I do see a glass fuel filter that absolutely has to go. If it's not leaking currently, it will be.
Yes they put two fuel pumps instead of original valve. Some of the rubber hoses were leaking where they clamped onto hard lines. So I removed it all, time to get it all safely buttoned up
 

jonbgood

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c20
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454
Update:
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I have removed it all. This is what they had going on connecting across both tanks. Also removed both fuel tanks because I have it parked in garage with water heater and was concerned about all the fumes the space was filling up with. So I figured I remove it all and inspect everything till I can get it all properly put back together. Also removed the Carburetor (one of those Chinese quadrajets) it wreaked of fuel sitting in it. The carb has no numbers or identification, I might switch to something else. Any suggestions?
 

75gmck25

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Assuming you still want dual tanks - The six port solenoids with only a single power terminal have been unavailable for several years. If you can’t find a NOS solenoid, then the best choice is to switch to the newer version with a six wire connector. There are articles on the net that explain how to convert.

I have my dual tanks working, but ended up buying a lot of ethanol resistant fuel line, and then have to keep all those hose connections tight. An alternative is to swap in a Blazer or Suburban tank in the back, and move your spare up into the bed. IIRC, they had three tank sizes, and the biggest was 40 gallons.
 

jonbgood

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east bay area , California
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Johnny
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1977
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c20
Engine Size
454
Assuming you still want dual tanks - The six port solenoids with only a single power terminal have been unavailable for several years. If you can’t find a NOS solenoid, then the best choice is to switch to the newer version with a six wire connector. There are articles on the net that explain how to convert.

I have my dual tanks working, but ended up buying a lot of ethanol resistant fuel line, and then have to keep all those hose connections tight. An alternative is to swap in a Blazer or Suburban tank in the back, and move your spare up into the bed. IIRC, they had three tank sizes, and the biggest was 40 gallons.
I’m just going to put one tank back in on passenger side to make it easier. I see they have a 20 gallon on rock auto, have to check if it will fit in place of the 16. With a new tank and fuel pump up front and carb with a new canister I’m hoping that will fix all my gas problems and hopefully it won’t wreak of fuel like it did before. I was nervous of keeping it in garage with water heater on how it was before. I don’t think the system venting properly and cheap Chinese carb was blowing fuel thru vacuum ports. Hopefully it all comes together.
 

SquareRoot

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Assuming you still want dual tanks - The six port solenoids with only a single power terminal have been unavailable for several years. If you can’t find a NOS solenoid, then the best choice is to switch to the newer version with a six wire connector. There are articles on the net that explain how to convert.

I have my dual tanks working, but ended up buying a lot of ethanol resistant fuel line, and then have to keep all those hose connections tight. An alternative is to swap in a Blazer or Suburban tank in the back, and move your spare up into the bed. IIRC, they had three tank sizes, and the biggest was 40 gallons.
How hard is it to switch the wiring up to work with the newer 6-port? Can't be that complicated. I'm running dual tanks with in-tank pumps controlled by EFI and throwing together a schematic was pretty easy.
 

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Grit dog

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My 77 original 1 tank with aftermarket 2nd tank has a 1 wire switching valve and works flawlessly.
Seems far less complicated than the OE setup on my 86.
If you have good tanks no reason not to rig it back up like that. IMO. It’s one of the cool features of these trucks. And gas doesn’t last long in these things!
 

jonbgood

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east bay area , California
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Johnny
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1977
Truck Model
c20
Engine Size
454
My 77 original 1 tank with aftermarket 2nd tank has a 1 wire switching valve and works flawlessly.
Seems far less complicated than the OE setup on my 86.
If you have good tanks no reason not to rig it back up like that. IMO. It’s one of the cool features of these trucks. And gas doesn’t last long in these things!
I have to empty one of the tanks full of old fuel and inspect it. Now you got me thinking maybe I should run them both. I was just going to buy one new tank. But if the two I have are still good maybe I should put them back if they have that 1 wire switch. Did you run two hard lines across to each tank? Thanks for advice , is your 77 all stock?
 

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