Fuel tank selector for 78

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RoryH19

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apparently its not sold anymore, I didnt realize the 3 port 1 wire was easier to find than the 6 port.


If you want to retrofit, there is a kit I just linked from SMP to use the later motorized valve with 6 ports, mounts in place and pipes the same. will last longer but requires more than swap.

Honestly, Im lazy enough to just use two 3 ports... lol. maybe ensure the power supply is better like relayed wi9th good gauge wire so the solenoid engages positvley every time and also if possible a filter in line before the valve for the send pipes would probably increase their life span.

Just an idea
Right, I've seen the 3 port or the newer 6 port style. I'll probably just go with the newer style and rewire where needed. I think I have to change the dash switch and the plug.
 

AuroraGirl

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Right, I've seen the 3 port or the newer 6 port style. I'll probably just go with the newer style and rewire where needed. I think I have to change the dash switch and the plug.
oh common you dont like the idea of improving on the oe 3 port by having twice as many failure points.. oh wait.. Lol.
That kit has a switch and the connector. if you want the right switch you only need to slightly file the opening and buy a new switch.
the kit probably doesnt even replace the OE, it probably uses the switch on the truck to switch the sender(I think) and the toggle to switch the tanks. i think. no idea.
You must be registered for see images attach

hmm
 

RoryH19

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oh common you dont like the idea of improving on the oe 3 port by having twice as many failure points.. oh wait.. Lol.
That kit has a switch and the connector. if you want the right switch you only need to slightly file the opening and buy a new switch.
the kit probably doesnt even replace the OE, it probably uses the switch on the truck to switch the sender(I think) and the toggle to switch the tanks. i think. no idea.
You must be registered for see images attach

hmm
Yeah, I'll pass on the 3 port :)
The 6 port wiring looks pretty straight forward. Just need to use an 81-86 switch I think.
 

bucket

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Wait... the single-wire 6-port is the one that's hard to find? I thought it was the 3-port that was hard to find?
 

AuroraGirl

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Wait... the single-wire 6-port is the one that's hard to find? I thought it was the 3-port that was hard to find?
It used to be, then it switched

ill see myself out

I know for a fact like early this year I recall being able to find plenty of those but no 3 ports. I almost bet you the Ac delco part does runs, sells out, stays that way for a while, then they run some and that was the end of those supplies

The rear window defroster/FM antenna module on the park avenue is a literal guarantee to be needing replacement after 50+k miles no matter what damn near, and i had people trying to pay me for mine when I only got it a month or two before them.

Then recently it came out of being "discontinued" and they are happy again

I also have a couple motorcraft parts for a 300 I may be wise to not put on mine and try and hustle.. lol
 

RoryH19

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It used to be, then it switched

ill see myself out

I know for a fact like early this year I recall being able to find plenty of those but no 3 ports. I almost bet you the Ac delco part does runs, sells out, stays that way for a while, then they run some and that was the end of those supplies

The rear window defroster/FM antenna module on the park avenue is a literal guarantee to be needing replacement after 50+k miles no matter what damn near, and i had people trying to pay me for mine when I only got it a month or two before them.

Then recently it came out of being "discontinued" and they are happy again

I also have a couple motorcraft parts for a 300 I may be wise to not put on mine and try and hustle.. lol
Yep.
I can find the 3 port, 1 valves on Amazon now or the newer multi wire 6 ports.
1 wire 6 ports must be out or discontinued.
 

Powerhouse Ranch

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Does anybody have a spare 6 port 1 wire selector valve laying around? Only thing keeping me from getting the '74 beast from up and running. Would kill for one. . .
 

AuroraGirl

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Does anybody have a spare 6 port 1 wire selector valve laying around? Only thing keeping me from getting the '74 beast from up and running. Would kill for one. . .
You can wire 2 3 ports or you wait for the aftermarket to pump out the next batch (who knows ) or you can do the upgrade to the 6 port oogles of wires which needs new switch n stuff
 

Juggernaut

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I ran into this problem a few years ago. I couldn't find the 6 port 1 wire. I found several 3 port 1 wire, but when I ordered them, they would come in with 5/16 fuel line fittings, even when advertised with 3/8. I finally went with the 6 port motorized switch and connector from Rock Auto. And the motorized switch has 5/16 return lines instead of the 1/4 used on the sending units, but I just had to make it work. The wiring is a little different, you have to run a third wire to the motorized switch, and you have to change the switch in the dash to a mid 80's switch
 

AuroraGirl

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I ran into this problem a few years ago. I couldn't find the 6 port 1 wire. I found several 3 port 1 wire, but when I ordered them, they would come in with 5/16 fuel line fittings, even when advertised with 3/8. I finally went with the 6 port motorized switch and connector from Rock Auto. And the motorized switch has 5/16 return lines instead of the 1/4 used on the sending units, but I just had to make it work. The wiring is a little different, you have to run a third wire to the motorized switch, and you have to change the switch in the dash to a mid 80's switch
if one was insistent on keeping the dash switch and wanted a solenoid and not a motorized valve, 2 3 ports and a 1980 delay relay would make a decently reliable system, but its a lot of fab/figuring out compared to just doing the newer setup or etc
 

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