So below I'm going to attach some pictures of the engine bay, but the connectors on the temp sensor on the thermostat look fine (also attached). Out at it right now and it starts on starter fluid but won't stay up.








This picture down at the bottom shows the two connectors that just exist. Not sure what they are. Or where they run.

 

That first and second pictures show corroded terminals. I would replace that sensor and connector like I got from NAPA years ago. The pins should be copper color.

I see the two connectors in the last picture, need to be connected as your air pump system is still working ? Those wires look messed up.

I think diggerrigger knows more about that system, maybe PM him t have him chime in.

 

Few other things, you need better battery cable and ground cable to the frame and the engine block. I had to open up the bolt holes on that negative cable, but it fits great.

 

The air pump is not infact hooked up. Ain't seized up neither which is funny. But yea I'm about to change out the terminals and ground. Figured out the dieing was from it running out of dinosaur juice. I have no idea why I didn't check that first lol. I got a great deal on an intake and carb so I think I'm going to just go with that at this point. Bypass the high pressure and put a regulator on it still just to be safe. Tired of all this computer stuff just give me a flat head screwdriver at this point :/

 

Mice have been chewing on your wiring. It will be pulling the whole harness out and repairing/checking it, or converting it like you said. You will need a HEI distributor and a carbed intake. You will need to re-wire your fuel pump, whatever you choose to use, since the fuel pump relay was fired by the computer. The computer will be gone, so you will need to redo that circuit.

 

3 things, chipmunks, already do, and already have the high pressure and rear fuel pump hooked to a switch in the cab cause something was being stupid and not letting them get fire 😃

 

So it will try and run on Dinosaur Fart but not on Dinosaur Juice? Do you watch "Taryll Fixes All" on Youtube love his videos and has helped me fix my weed whackers that are 20+ years old.

So can you check the fuel PSI so you know that it is getting the right PSI?
You may hear the pump(s) but it may not be building PSI.
Dave ----

 

No I do not but I sure will try it now.
And the only fuel pressure tester I could find was not wanting to read on any vehicle so meh. Plus I'm pretty sure it was outta gas because I put like 2 gallons in it and it ran again so I'll call it a win lol

 

Alright we are back with a little less wiring, a new intake manifold, and a Holley double pumper.
I just got a couple questions:
A- Is the coolant temp sensor for the gauge cluster really that little sensor that is just a plug on nipple?
B- Does anyone know how much fuel pressure the in-tank fuel pump alone makes?
I feel like I had more questions but I forgot so thank yall in advance again

 

The gauge sensor should be a 1 wire push on that was in the intake, not the multi wire one at the Tstat housing.
If you have a test light, key on and check the wire the light should blink. If you ground that wire the gauge should move to hot.

Depending on the sysem it could be a low PSI or a high PSI pump in tank.
How many pumps dose the truck have, 1 in tank and 1 on the frame rail or just the one in the tank?
If 2 pumps the intake would be a low PSI pump but I dont know if it is low enough for a carb?
If 1 pump then it is a high PSI and will not work with a carb with out a regulator that can drop the PSI down to 5 PSI MAX.

Now if a regulator will not work with the in tank pump I dont see why you could not pull the sender, remove the pump and extend the pickup to reach the bottom of the tank like the pump did.
Then take the power wire from the tank pump to power a low PSI frame mounted pump that would work like the in tank pump did. Prim when the key was first turned on to fill the carb and then once motor was running the computer would tell the pump to run all the time. Also all the safety items are in place like the crash switch to turn the pump off.
Now when you extend the pick up you cant use normal rubber hose as the outside dose not stand up to being in gas all the time and will fall apart.
Try and use hard line like brake line and use a compression fitting to join them to make it longer.
Dave ----
Dave ----

 

Yea that's what I meant about the intake sensor
It has three pumps, one in each tank and one on the rail. I figured the in-tanks would be lower and was planning on bypassing the high pressure on the rail anyways but couldn't really find which one it is. I got a pressure regulator just because I figured even with the bypass it would be too strong and flood my carb out.
Oh I also just remembered my other question.
Is the fuel line normally 1/4inch? Mine is NOT factory from the looks of it as it is like a plastic (?) fuel line. Makes the toll of it sitting for over a decade not as bad I guess but its a pain in the *** trying to get the regulator to actually cooperate.

 

Being I am not up on the EFI fuel system I am sure someone will be by to give the right answers if mine are wrong

Being you have 3 pumps the in tank one would be the low PSI ones but I dont know what the PSI would be?
Could always put a gauge on it and see what the pump(s) put out and you would know then.

Now being you have dual tanks and the truck was EFI it most likely has a return to each tank. I dont know how that would play into this carb swap deal?
Same if you had to run a return from the added regulator back to each tank that is being used?
Could you pick up fuel to the carb after the switching valve, say where it hooked into the fuel rail, to feed the carb and like you said bypass the high PSI pump?
I would think if you had to run a regulator the EFI return should be close by to use.

From what I seen posted the later truck and thinking all EFI trucks use the plastic fuel line.
I think someone posted that they were able to use rubber fuel line on to the plastic line and use a clamp but just could not over tighten or the line would be crushed and leak.
Now I have used plastic line for air with compression fittings to join them and a metal insert, it had a little flare on the end so it would not fall inside the plastic line, was put in the plastic line and would keep the plastic line from being crushed.
Might be able to come up with something like the insert and then not worry about crushing the plastic line.

I am sure others have a better answer for this line
Dave ----

 

Plastic fuel lines are stock. They last pretty good compared to rubber. If you need to add or change any lines I would use Ni-Cop line or steel. The supply line is 3/8, the return line is 5/16. On my little Bronco, both lines are 5/16.

Even though the in tank pumps are low pressure, I do not know if they have internal regulators in the pumps, I doubt it. So a regulator would be a good idea, get one that is 3 port with a return and you can hook to your return line and keep the fuel circulating. You will have to add a inline filter if you stop using the one mounted on the frame.

 

When I tested the pressure of my truck's two in-tank pumps they were thirty-five years old. Both pumped at 3 psi.

Homemade inline test gauge.


IMHO, you will need to eliminate the ECM control of the fuel system. There are four wires at the fuel pump relay. The on/off is controlled by the ECM. The red is power from the ECM. The tan/ lt green is the ground.

The plan: Disconnect both from the relay leaving the yellow and the pink as is. Ground the terminal on the relay that the tan/lt green wire was plugged onto. Run a wire from ignition on circuit to terminal the red was plugged onto. This will trigger the pumps power when the key is turned to on.

Remove the high pressure frame rail pump and replace with a suitable electric carb pressure pump. Edelbrock and Holly make them. Use existing wiring.

Leave the rest of the fuel system as is.

I believe there is no way your truck's ECM is going to run the existing fuel system or the TFI ignition now that a portion of the EFI components are deleted.

Edit: I forgot to address the FPR and return. The FPR left with the EFI stuff. I think the carb fuel pumps are designed for 5 to 7 psi so no regulator would be necessary. Just dead head the fuel line from the new lo pressure rail pump to the carb. In which case you would plug the return FROM fuel rail at the Dual Function Reservoir. Or keep it with a regulator after the carb if needed.

The original high pressure frame rail pump (capable of up to 100 psi head) would probably work with a regulator throttled back to 7 psi (or what the carb manufacturer specifies)

Another edit: The fuel gauges draw power from separate ignition on circuit.

 

If you need, the guy's at NAPA can make up the plastic fuel lines, just bring in the old one and they match it up. Here's how I fixed a leak in one of mine a few years back.