i added an electric lift pump to my 86. couldn't find a hot terminal that would turn off/on with the key in run position.

any suggestions ? i have the pump wired to a manual switch for now, would like it hooked to turn on when key is in run.

GPs are manually switched,

thanx

 

i would wire it with a relay.and maybe use the shut off solenoid on the ip for the trigger wire

 

Use a relay with main power from the battery through a fuse.
Light green wire with red stripe behind the passenger side battery is the ignition circuit.
Use that wire for the trigger circuit.

The other option is the fuel shut off solenoid, front terminal drivers side of the IP.

 

cool.

thanks loads guys.

 

ok this looks good and easy thanks.
is the relay needed when using the fuel shut off solenoid's hot?

 

The fuel shut off solinoid wire will trigger the relay to close the relays contacts to power your pump.

 

The red/green wire is the same wire that goes to the FSS.
So no matter where you tap into it at, you should use a relay and only use the FSS wire to trigger the relay.

The red/green ignition wire already powers several things under the hood, and the electric fuel pump may just increase the load enough to blow a fusible link at the wrong time.

 

ah ok.i didn't think it drew enough to worry about.but this feed already has some draw so il put in the relay then.thanks.iv got a 30a relay.i grabbed an inline fuse holder too just to be safe.i needed some 15a fuses so il toss one of these in for now,but im guessing i should replace it before i start going anywhere with the truck (once on the road) with a 10a probably? and the fuse should go between the relay and the pump correct?

 

I would put the fuse closest to the battery voltage, so between the 12v source and the relay. That way your protected if the relay shorts out or the hot wire shorts out down the line somewhere.

 

On the 93 trucks, the ignition circuit is sending power to the glow plug relay ignition terminal, the fuel heater, the cold start timing advance solenoid, the cold start high idle solenoid, possibly the alternator depending on which one you have and the fuel shut off solenoid.

So even though it works fine if you add the electric fuel pump, when the temp is below 32 degrees, it might add just enough load to blow a fusible link.

If your luck is like mine, it will happen at the worst time and location.

Battery positive terminal to fuse to relay positive power in terminal.
The relay power out terminal to the fuel pump.

Some of the ignition wires are red/yellow on the newer trucks.

 

ok,i spliced into the fuel shut off solenoid.placed a pigtail back into the connector so that remains as it was.from the splice,i connected my inline fuse.from the other side of the fuse,i placed the 30a relay using the + in.from the other side,i connected to the line that goes to the fuel pump.and didn't use the 3rd wire in the relay.
so this is wrong then?
i want to run a line over from the + bat terminal into the fuse.then out from the fuse,to the + in of the relay.then with the other two wires,i want one to the pump,and the other to the fuel shut off solenoid right?

as it is now.it works.tho i guess its to no advantage lol oops.
iv got water in the lines and she's not starting.(frozen water) i blew the delivery line out,but the return is still blocked.
got my fuel selector valve hooked up correctly too,but the gauge isn't working.(it is sucking from the main tank with the switch on front tank.it will return to it too fine too,im sure,as i didnt cross those up.once i get the ice out.)
with it switched to the front tank,it draws from the front tank.and this tank is full.the gauge shows empty.
when i switch to the rear tank,it should suck from it fine,tho didn't check.but i know its not crossed with the delivery,so it must be right.the rear tank i plugged into R and front i plugged into L.
the gauge goes WAY over Full mark(a pretty much empty tank).
man what a time lol.
im getting it all ready so i can back under my new flatbed to put it on.hopefully all goes good tomorrow.

i followed post# 8 here.and all colors where same as my truck:
https://www.ford-trucks.com/forums/6...g-diagram.html
i dont really know if the gauges worked correctly before or not.i thought so tho.

 

Check in the under dash fuse box, there is a fuse for the fuel gague and selector valve. I'm not sure but I think it is no. 5.

 

I am going to assume you used one of the small 30 amp relays for driving lights.
The terminals should be labled.

30 – the power lead from the battery goes here (for the high amp device)

85 - this is the ground side of the coil… wire this to a chassis ground

86 - this is the power lead to actuate the relay coil (from the switch)

87 - this is the hi amp output to the device

To install this relay it would be wired like this.

Battery positive to fuse to relay terminal 30.
Relay terminal 87 to electric fuel pump positive lead.

Relay terminal 86 spliced into FSS wire.
Relay terminal 85 to ground.

If relay terminal 85 is not grounded, the trigger coil will not work to close the relay.
So no power will go to the electric pump.

Some of those small relays have a fifth terminal, 87A.
Those are SPDT (single pole double throw) relays.
On those relays the wiring is the same, except terminal 87 is hot when power is applied to terminal 86, terminal 87A is hot when no power is applied to terminal 86.
You have to be careful with relays with 5 terminals because what ever is on terminal 87A is on when everything should be off.

 

yeah,they're both fine.the gauge an fsv fuses.
i think i may need new sending units.

yeah.that's what i got.cool.this is easy to follow.i'l be sure to change it like this tomorrow so im all done with this.
thanks a mill.

 

What ever you do, DON'T just tap into the FSS wire on the IP. That's what I did a couple of days ago and smoked a few wires. I connected the fuel pump to the battery and toggle switch and end of problem. Tomorrow I go get a relay and fuse and switch and permenently fix the problem.