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

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SquareRoot

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You used the weather packs for the trailer wiring? Or for the fuel pump wiring?
Both. I plan on replacing every factory external connector with WP's eventually. I hate troubleshooting electrical issues. WP's are once and done.
 

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This. Bought a robust kit. One of those items I wish I'd bought 10 years ago.
 

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That’s a nice kit
 

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Powered it up today with engine off to pressure check everything. All good......for about......3 minutes and then all h*ll broke loose. The factory steel lines started popping pin hole leaks and spraying fuel all over the frame rail. F**k..! Sourced a 25 ft roll if 5/16 and 3/8 line today. Replacing the factory lines is gonna be a pita! I figured those rust free OEM steel lines could handle the 65psi of EFI. Wrong!
 

Dleslie212

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Powered it up today with engine off to pressure check everything. All good......for about......3 minutes and then all h*ll broke loose. The factory steel lines started popping pin hole leaks and spraying fuel all over the frame rail. F**k..! Sourced a 25 ft roll if 5/16 and 3/8 line today. Replacing the factory lines is gonna be a pita! I figured those rust free OEM steel lines could handle the 65psi of EFI. Wrong!
Fuuuuuck. Better than when you’re miles from home though
 

AuroraGirl

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Not wanting to mess with this anytime soon, I ran new wires front to rear and replaced the 40 year old loom. I included new wiring for a seven pin trailer connector as well. Bought a weather pack terminal kit and did it right. I absolutely love how easy and functional those weather pack connections are.
good choice. Like, incredibly. Im proud of you even. Did you find a weather pack with enough slots or did you use 2+ bodies to connect. some connector grease will keep them able to open in the future too lol. Also if you can find something like wide electrical tape or just something that isnt too sticky when taken off, you should simply wrap the whole body like to keep water dirt etc out but in such a way it unwraps like you never left it for 10 years etc. That is something I would find probably huge for the plastic quality years to come.

also an LS Swap would be proud.
 

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on anti squeek. If you can't get them could you not use a bicycle inner tube cut to create a long strip of two ply rubber and use it? Just thinking. Then trim the sides if need be if they hang out and look like crap.
 

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Here you go.
Hey buddy. So I have both my tanks installed, all the plumbing ran and everything ready to go except wiring, which I decided to attempt to tackle today.

Looking at your diagram, I can just ground the two pump grounds to the frame, in the same place I grounded my senders to? I hope you or somebody good with electric sees this because I need a lot of help. Lol
 

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And another question, because I'm trying to understand how this works. Does this setup mean that the power to both pumps is always active, but we're activating whichever pump we want to run by turning the ground off/on?
 

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Hey buddy. So I have both my tanks installed, all the plumbing ran and everything ready to go except wiring, which I decided to attempt to tackle today.

Looking at your diagram, I can just ground the two pump grounds to the frame, in the same place I grounded my senders to? I hope you or somebody good with electric sees this because I need a lot of help. Lol
Correct. That's what I did. The output of the EFI is also a ground signal but it controls the signal side of the relays thru the on-off-on switch.
 

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And another question, because I'm trying to understand how this works. Does this setup mean that the power to both pumps is always active, but we're activating whichever pump we want to run by turning the ground off/on?
Exactly. The power to the pumps must be on with the ignition, not the battery.
 

Dleslie212

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Correct. That's what I did. The output of the EFI is also a ground signal but it controls the signal side of the relays thru the on-off-on switch.

The output of the EFI being the two wire pigtail that is meant for the fuel pump? I'm assuming it's the same wiresninhad connected to my previous external pump that was pulling through the six port valve
 

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The output of the EFI being the two wire pigtail that is meant for the fuel pump? I'm assuming it's the same wiresninhad connected to my previous external pump that was pulling through the six port valve
Yes, but the pigtail has both a positive and a ground, You will only use the ground. The simplest way to run the positive side was a single 12 gauge wire. I plugged mine into an open IGN slot in the fusebox. The other end is a splice that feeds both #30 pins on the relays and the #85 tabs.
 
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Dleslie212

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Yes, but the pigtail has both a positive and a ground, You will only use the ground. The simplest way to run the positive side was a single 12 gauge wire. I plugged mine into an open IGN slot in the fusebox. The other end is a splice that feeds both #30 pins on the relays and the #85 tabs.
Do you have any pictures of how you mounted those relays or anything? What did you do with your PF4 pigtail to get the ground? Did you cut the connector off? What did you do with the positive wire, just tape it up or something?And how did you know which of the two wires was the ground?
 

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Do you have any pictures of how you mounted those relays or anything? What did you do with your PF4 pigtail to get the ground? Did you cut the connector off? What did you do with the positive wire, just tape it up or something?And how did you know which of the two wires was the ground?
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.
 

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