Electric Fuel pump wiring (??)

Electric Fuel pump wiring (??)

manitou

Jeeper
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Location
Missouri & Colorado
Vehicle(s)
1983 CJ5 I6 258 4-spd. manual Dana-30 frt; AMC-20 rr. Stock/orig; Red w/new Bestop soft top.
Reman 258 motor being dropped in my '83 CJ5 this week. Because I'm a little uncomfortable with wiring issues, I had the shop add an electric fuel pump to the quote. Not being an absolute necessity...I passed on their price. A little research, and I have the confidence that I can do this myself (for a lot less than the quote). So, according to the many wiring diagrams that I've seen, I need to connect the "NO" (Normally Open) terminal on the pressure safety switch to the ignition switch. Here's my question: Does this mean that I have to dig into the steering column to access the ignition switch terminal? Or...is there an ignition switch wire that I can tap into under the dash, or under the hood? Thanks for any help you all can provide.
 
From my experience, with a carbed engine, a mechanical fuel pump is quite sufficient. Usually an electric pump puts out a lot more pressure and can push past a needle and seat assembly in a carb. Make sure the line from the tank has no cracks as they will present problems with any type of pump. Also an electric pump is kinda tricky to properly set up. Are you having fuel delivery problems?
 
Depends on the amperage of the pump...

To be safe, I tapped off the cigarette lighter (ignition controlled) and ran that to a relay in the engine compartment, then relay to pressure switch. I haven't bought my pump yet... have been deciding between two Holley Mighty Mite models (1-4 psi vs 4-7 psi). I do have the pressure switch and the wiring run.

Converted the cigarette lighter to a USB charging port.

I've got a Weber carb.
 
The best place to mount a pump would be at the lowest point in the fuel system, like near the transfer case. This way the fuel will siphon itself to the pump then the pump will do the rest of the work. Another location would be as close to the pump as possible. Either way, a low restriction fuel filter is required prior to the pump to protect it from any debris in the tank. Running out of gas or even to a low level can burn up a pump. The gas tank vent system must be working properly so the siphon process can work. I once had a fuel tank sock clog up and had to bypass it and run a spare fuel line directly into the fuel filler hole from the pump.
 
From my experience, with a carbed engine, a mechanical fuel pump is quite sufficient. Usually an electric pump puts out a lot more pressure and can push past a needle and seat assembly in a carb. Make sure the line from the tank has no cracks as they will present problems with any type of pump. Also an electric pump is kinda tricky to properly set up. Are you having fuel delivery problems?

For the most part, my CJ is a weekend vehicle. After sitting for 5 or 6 days, I usually have to give it a shot of starter fluid to get it going. Also, the pump I purchased is low pressure (2.5-4psi), which is recommended for my Weber 32/36.
 
For the most part, my CJ is a weekend vehicle. After sitting for 5 or 6 days, I usually have to give it a shot of starter fluid to get it going. Also, the pump I purchased is low pressure (2.5-4psi), which is recommended for my Weber 32/36.

I've got a Webber and regular fuel pump. Only after a couple of weeks do I have any problems sitting there that long, 5-7 days no real problem. Do you have a good working choke ? I installed a manual choke and that really helped with the Webber
 
I've got a Webber and regular fuel pump. Only after a couple of weeks do I have any problems sitting there that long, 5-7 days no real problem. Do you have a good working choke ? I installed a manual choke and that really helped with the Webber

After the motor swap this week, I'll see how she runs. I replaced the electric choke and mechanical fuel pump about six months ago. That seemed to help a little. I just wanted to have the electric pump on hand and ready to go if, after the first prolonged down-time, I have to resort to the starter fluid.
 
For the most part, my CJ is a weekend vehicle. After sitting for 5 or 6 days, I usually have to give it a shot of starter fluid to get it going. Also, the pump I purchased is low pressure (2.5-4psi), which is recommended for my Weber 32/36.

Sounds like the carb float bowl vent is open. The later CJs had a valve that would close off to prevent evaporation in the float bowl. I am not sure if the Weber has anything like that. I have heard of guys installing electric fuel pumps just for that reason though.
 
Stock like engine in a CJ doesn't need a ele fuel pump.
IF you do use one. Mount it as goes to the fuel tank as you can.
Run a dedicated circuit for it, triggered buy the ign.
LG
 
Wiring isn’t scary. Fuses are your friends!
Your fuse block is divided into two halves. One half has power all the time, the other is turned on / off with the key.
In this case you want to use the “key on” side. Using a meter or test light, select a suitable location in the fuse block. Run a wire to an inline fuse of 1 amp, then from there to a relay coil. The other side of the coil goes to ground.
Run another wire from your positive battery into a fuse (slightly higher amperage than what your pump draws) then to the common terminal of the relay. The output terminal of the relay goes to the positive wire on the pump. The other wire on the pump obviously goes to ground.
Most electric pumps push, not pull. Therefore they need to be mounted as close to the tank as possible and below the fuel level! There is only slight suction and you need to create a siphon.
Make sure your tank is vented... possibly thru the charcoal canister.
Remember if you mess up somewhere the only danger is a blown fuse. That’s why they are there. It’s not a big deal... you can do this!
 

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