Electric fuel pump wiring

buds56

Junior Member
I'm working on a 53 Customline, this is my first Ford and the first time dealing with a 6 volt positive ground.

I bought an electric fuel pump for it to prime the system after sittting for extended periods of time.

My question is should I put the + terminal to ground and power the negative terminal?

I just put a new harness in the car and everything works well but this puzzles me.

Thanks, Bud
 

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My question is should I put the + terminal to ground and power the negative terminal?
Thanks, Bud

Yes. If the positive battery post is hooked to ground then you run the positive pump wire to ground and power the other wire that might normally run to ground. Here's mine
Fuelpumpelectric.jpg

Note positive pump wire to ground and negative from switch.
 
Old Henry

Is that the Carter 6V unit Macs sells with the inline filter?



No. It's an AIRTEX E8902 6 VOLT FUEL PUMP 2.5psi-4psi 25gph-30gph Inlet Outlet 5/16 Free Flow POSITIVE or NEGATIVE GROUND available several places including here: http://www.ebay.com/itm/AIRTEX-E890...t=Vintage_Car_Truck_Parts_Accessories&vxp=mtr


I wouldn't put an in line filter under the car where I have my pump installed. It would be very hard to change. I actually don't use an in line filter at all. I just use the old settling bowl that never plugs up, is easy to monitor and clean out when anything gets in there. The smaller cannister that comes with this pump is not an in line filter. It is the one way valve that makes the pump work.
 
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Thanks!

I had a wonderful experience last night that I'm sure many flathead owners have had. I drove to work, and then to cruise night for a local a club. When I went to leave had no gas from the pump. Swapped a spare pump known to be good that I had in the trunk, ran for 5 minutes then stalled again so I thought I had a plugged fuel line since it had just been filled up with gas for probably the first time in 40 years. When the rollback truck came to get me and started to load the car (trunk first), fuel started running out all over the place siphoning out of the tank... so that ruled out a plugged gas line.

My pump has suction when I depress the arm on the bench and I have another Airtex 591 (metal bowl) with a new diaphragm. So I figure the electric will be a backup at the least.
 
I also have the airtex e 8902 that I use as backup only. A few days ago I made up a line between mechanical pump & carb so I could check pressure of the pump that I had rebuilt it was 3psi. idling or reved up, I was happy so I thought I would check on the airtex pump while I was at it, it was 6psi. so if you are going to use it as your primary you should put in a regulator.
Gary.
 
Buy a good mechanical pump and forget the electric pump. I can leave my hot rod sit for months and it will start with no problem. My brother use to blow in the tank while I cranked the engine after the car sat for a few days to prime the pump. I bought a new pump from Mac's three years ago and have had no problems.

After the car has sat for a while, I open the hood and watch fuel flow into the sediment bowl. I use the button on the bottom of the solenoid.

Installing a electric fuel pump on a flat head is an old way to solve a worn out mechanical pump and is kind of folklore. When in high school there were a bunch of kids with flat heads and nobody ran a electric fuel pump. I think you are wasting your time and money and maybe feeding your ego.

Positive to positive and negative to negative- If the postive battery cable goes to the frame the positive wire from the pump goes to the frame.
 
Buy a good mechanical pump and forget the electric pump.

The best newest mechanical pump in the world won't pump vaporized gasoline. I'm talking about vapor lock that plagues some flatheads in heat. An electic backup pump is a very apporpriate solution for that temporary problem.
 
I'm new to the flathead and working on old cars so I'm on a learning curve here.

I just installed a rebuilt 8BA carb on my '53. I assume that the fuel pump had completely emptied (gas coming out of the line) when I pulled the fuel line from the old carb before removing it.

After installing the new carb I noticed that the sediment bowl (still full of gas) on the single action fuel pump had some junk in the bottom so I removed the bowl and emptied it. I notice that there is no filter in the bowl but the cork gasket seemed ok so I cleaned and reinstalled the bowl with the cork gasket.

Now the sediment bowl is empty, and with no gas in the pump, how do you prime the fuel pump?

Also, are the OEM type filter screens and bowl gaskets available at a regular retail parts outlet? I see that Mac's has them but places like NAPA and Advance Auto Parts don't show them on their web sites.
 
I'm new to the flathead and working on old cars so I'm on a learning curve here.

I just installed a rebuilt 8BA carb on my '53. I assume that the fuel pump had completely emptied (gas coming out of the line) when I pulled the fuel line from the old carb before removing it.

After installing the new carb I noticed that the sediment bowl (still full of gas) on the single action fuel pump had some junk in the bottom so I removed the bowl and emptied it. I notice that there is no filter in the bowl but the cork gasket seemed ok so I cleaned and reinstalled the bowl with the cork gasket.

Now the sediment bowl is empty, and with no gas in the pump, how do you prime the fuel pump?

Also, are the OEM type filter screens and bowl gaskets available at a regular retail parts outlet? I see that Mac's has them but places like NAPA and Advance Auto Parts don't show them on their web sites.

My stock mechanical pump will pump the gas from the tank to it if the battery doesn't die first. Might work with yours. Takes a while, just keep cranking.
 
Old Henry

Sorry to bug you again but I've got my electric pump installed in the line and it primes the mechanical pump and the carb just fine. But about 1/2 mile down the road my engine starves and I have to turn on the electric pump again for a few seconds. Is your mechanical pump able to pull fuel through the electric pump when it's switched off?
 
Old Henry

Sorry to bug you again but I've got my electric pump installed in the line and it primes the mechanical pump and the carb just fine. But about 1/2 mile down the road my engine starves and I have to turn on the electric pump again for a few seconds. Is your mechanical pump able to pull fuel through the electric pump when it's switched off?

Yes. I only turn my electric pump on for a few seconds - long enough to solve the problem - then turn it off so most the time it's off. You might have a problem with your mechanical pump that needs checking out.
 
Old Henry

Sorry to bug you again but I've got my electric pump installed in the line and it primes the mechanical pump and the carb just fine. But about 1/2 mile down the road my engine starves and I have to turn on the electric pump again for a few seconds. Is your mechanical pump able to pull fuel through the electric pump when it's switched off?

I fitted a 6V 2-3 1b Carter pump just to prime the carb for starting and had to install a bi-pass valve as the mechanical pump couldn't supply fuel over about 35 mph due to the resistance through the pump. With the bi-pass valve it works fine. I understand the Airtex pumps have no restriction and there isn't a problem.
 
I fitted a 6V 2-3 1b Carter pump just to prime the carb for starting and had to install a bi-pass valve as the mechanical pump couldn't supply fuel over about 35 mph due to the resistance through the pump. With the bi-pass valve it works fine. I understand the Airtex pumps have no restriction and there isn't a problem.

Airtex is what I use with no problem.
 
I installed the carter on my 55 and it would not get enough fuel after about 35 40 mph..Built a bypass so it could get fuel around the electric an car ran like apeice of know what..Taking the bypass out and will just let the carter run if it needs fuel..Had an air tec and it dont work at all but the one on my 36 works great so??
 
Old Henry

Sorry to bug you again but I've got my electric pump installed in the line and it primes the mechanical pump and the carb just fine. But about 1/2 mile down the road my engine starves and I have to turn on the electric pump again for a few seconds. Is your mechanical pump able to pull fuel through the electric pump when it's switched off?

Your cam or rod may be worn. I understand in old days guys would either weld a spot on rod or add a washer on top.
 
Adileo, that post is from 2012 (8 years ago) and Old Henry don't do much posting on the Barn these days. Still might be good information for someone.
 
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