EFI Dual Tank Conversion, need help on power 4 the pumps.

Disclaimer: Links on this page pointing to Amazon, eBay and other sites may include affiliate code. If you click them and make a purchase, we may earn a small commission.

Dleslie212

Full Access Member
Joined
Sep 2, 2019
Posts
243
Reaction score
149
Location
Phoenix
First Name
Dustin
Truck Year
1977
Truck Model
K10
Engine Size
5.7L 350
I haven't mounted the relays yet, there just coiled up and zip tied. I'll be adding a weather proof relay box that holds 6 relays/6 fuses.

Your pigtail should not have any connector on the end? See photo. All you need is the tan/white wire. That's the ground output that controls the relays via the toggle switch. Disregard the orange wire. Just make sure the end is protected so it doesn't short out if it touches metal.
Mine def has a connector. When I ordered my original fuel pump, I had to find a connector that matched to wire it into the pump. I'll post a picture when I get back home
 

Dleslie212

Full Access Member
Joined
Sep 2, 2019
Posts
243
Reaction score
149
Location
Phoenix
First Name
Dustin
Truck Year
1977
Truck Model
K10
Engine Size
5.7L 350
xc_hide_links_from_guests_guests_error_hide_media

Here's a few pictures of the connector off the PF and the pump
 

SquareRoot

Full Access Member
Joined
Mar 18, 2017
Posts
4,192
Reaction score
8,030
Location
Arizona
First Name
Mike
Truck Year
85
Truck Model
K20
Engine Size
350
Mine def has a connector. When I ordered my original fuel pump, I had to find a connector that matched to wire it into the pump. I'll post a picture when I get back home
I see. That's just a 2 tower weather pack connector. You can either buy a pigtail for it at local parts store (I bought one from O'Reilly) or cut it off, install a ring terminal and connect it to the center post of the on/off/on switch. I'm talking about the tan/white, ground wire.
 

Dleslie212

Full Access Member
Joined
Sep 2, 2019
Posts
243
Reaction score
149
Location
Phoenix
First Name
Dustin
Truck Year
1977
Truck Model
K10
Engine Size
5.7L 350
I see. That's just a 2 tower weather pack connector. You can either buy a pigtail for it at local parts store (I bought one from O'Reilly) or cut it off, install a ring terminal and connect it to the center post of the on/off/on switch. I'm talking about the tan/white, ground wire.
Cool, thank you. I'm looking back a few pages at the diagram you drew for me - how do you have this wired into your fuel selector valve?
 

SquareRoot

Full Access Member
Joined
Mar 18, 2017
Posts
4,192
Reaction score
8,030
Location
Arizona
First Name
Mike
Truck Year
85
Truck Model
K20
Engine Size
350
The fuel selector valve switch and wiring all remain untouched. The switch only controls the 6 way valve and sending unit for the fuel gauge.
 

Dleslie212

Full Access Member
Joined
Sep 2, 2019
Posts
243
Reaction score
149
Location
Phoenix
First Name
Dustin
Truck Year
1977
Truck Model
K10
Engine Size
5.7L 350
The fuel selector valve switch and wiring all remain untouched. The switch only controls the 6 way valve and sending unit for the fuel gauge.
So the power wires for the dual pumps aren't being routed through the selector valve?

I do appreciate the help and I'm not a moron I swear lol... Electrical just doesn't click very well in my brain unless I really map it out in my head
 

SquareRoot

Full Access Member
Joined
Mar 18, 2017
Posts
4,192
Reaction score
8,030
Location
Arizona
First Name
Mike
Truck Year
85
Truck Model
K20
Engine Size
350
So the power wires for the dual pumps aren't being routed through the selector valve?

I do appreciate the help and I'm not a moron I swear lol... Electrical just doesn't click very well in my brain unless I really map it out in my head
No. Power comes from the ign power wire that you will add.
 

Dleslie212

Full Access Member
Joined
Sep 2, 2019
Posts
243
Reaction score
149
Location
Phoenix
First Name
Dustin
Truck Year
1977
Truck Model
K10
Engine Size
5.7L 350
No. Power comes from the ign power wire that you will add.
So are you using two separate switches? One to control which pump is currently powered, and another to control the six port valve and fuel gauge?
 

SquareRoot

Full Access Member
Joined
Mar 18, 2017
Posts
4,192
Reaction score
8,030
Location
Arizona
First Name
Mike
Truck Year
85
Truck Model
K20
Engine Size
350
So are you using two separate switches? One to control which pump is currently powered, and another to control the six port valve and fuel gauge?
Yes. The factory rocker switch in the dash controls the 6 way valve, nothing changed there. The on/off/on toggle switch only controls the power to switch the fuel pumps.
 

Dleslie212

Full Access Member
Joined
Sep 2, 2019
Posts
243
Reaction score
149
Location
Phoenix
First Name
Dustin
Truck Year
1977
Truck Model
K10
Engine Size
5.7L 350
Yes. The factory rocker switch in the dash controls the 6 way valve, nothing changed there. The on/off/on toggle switch only controls the power to switch the fuel pumps.
That makes more sense. Most ofy confusion was thinking you had everything going through a single switch
 

Dleslie212

Full Access Member
Joined
Sep 2, 2019
Posts
243
Reaction score
149
Location
Phoenix
First Name
Dustin
Truck Year
1977
Truck Model
K10
Engine Size
5.7L 350
Just an update - FINALLY finished everything this morning. It went from what I thought would be a one week upgrade to close to three months. New fuel tanks, brackets, straps, pumps and senders. New fuel filler hoses on both sides. All new fuel line up to the Pro Flo 4 system and back again. I just got back from a three or four mile test drive, and to fill both tanks all the way up to check for leaks. Other than a threaded AN-6 fitting that I forgot to tighten, no leaks. Everything started right up. The only difference now is that I have to hit two switches simultaneously while running in order to switch tanks - one to switch the six port valve and the other to switch pumps. I do like that the pump switch has an off spot, which can act as a sort of kill switch to be protect against theft.

Now it's time for cleanup, and next weekend will be cleaning up wiring and making everything look like it's not spaghetti. But I wanted to thank everyone here for the the help, ESPECIALLY SquareRoot - your help, patience with me and knowledge were invaluable

Edited to add that I do believe my fuel system is ready for an LS swap, if I decide to go that route in the future
 

SquareRoot

Full Access Member
Joined
Mar 18, 2017
Posts
4,192
Reaction score
8,030
Location
Arizona
First Name
Mike
Truck Year
85
Truck Model
K20
Engine Size
350
Just an update - FINALLY finished everything this morning. It went from what I thought would be a one week upgrade to close to three months. New fuel tanks, brackets, straps, pumps and senders. New fuel filler hoses on both sides. All new fuel line up to the Pro Flo 4 system and back again. I just got back from a three or four mile test drive, and to fill both tanks all the way up to check for leaks. Other than a threaded AN-6 fitting that I forgot to tighten, no leaks. Everything started right up. The only difference now is that I have to hit two switches simultaneously while running in order to switch tanks - one to switch the six port valve and the other to switch pumps. I do like that the pump switch has an off spot, which can act as a sort of kill switch to be protect against theft.

Now it's time for cleanup, and next weekend will be cleaning up wiring and making everything look like it's not spaghetti. But I wanted to thank everyone here for the the help, ESPECIALLY SquareRoot - your help, patience with me and knowledge were invaluable

Edited to add that I do believe my fuel system is ready for an LS swap, if I decide to go that route in the future
Awesome. Glad I could help. I've only been running my new system for a couple weeks. I still need to add a new tank/pump on the driver side but it's all wired and ready to plug in.
 

Forum statistics

Threads
44,167
Posts
950,745
Members
36,282
Latest member
Doug Hampton
Top