Do djet fuel pumps ever have the fuel pump portion go bad and not the motor portion? Mine is pumping more fuel out the return port than it is out the high pressure port. I pulled it apart and everything looks to be ok, but maybe it's just worn out. I have the pump out of the car and I was bench testing it so I'm sure it's not just incorrectly plumbed or wired.

I'd like to put a new pump under the gas tank, but I would need to run new fuel lines to take the pressure to do that and I was just hoping to get it up and running to make sure everything is working ok before I jumped into a project like that.

Just go with the single in / single out pump used on the '75 - '76. Cheaper than the 3 port.

SS lines are not that hard to install with the engine out. 3/8" supply, 5/16" return.

Your check valve in the 3 port pump could be weak / broken. Usually they will leak around the electrical connector. They can be rebuilt, but why? ANY pump that puts out 30+ PSI is potentially useable (I forget the liters/min output required ... your Haynes manual has that info).

I had the problem you describe and figured it is the rubber piece on the centerline side of the pop off valve. It sticks in the bypass mode instead of moving out when the fuel starts flowing. That valve, from what I have gathered, was intended to shunt air in the line to the return rather than pressurizing it to the fuel rails. The air doesn't have enough pressure to move out the pop off but fuel does. When the rubber tit gets sticky even the fuel doesn't have enough pressure to move the pop off out. I never found a solution. No rubber kits available - had to write off the pump.

My pump had the same problem. IIRC I fixed it by swapping out the spring in the bypass valve "bump" (that is normal to the ports) with a stiffer one from another pump with a seized motor.

I just went through this. Toss that 3 port pump out and get a 75-76' FI pump as stated. It simplifies the install and they are avail new still.

In another post someone said something about buying prebent fuel lines for the tunnel. Where can you get them at, and if I were to make them myself what sort of flare should I use on the ends to make sure the high pressure rubber lines stay on?

Also if anyone needs a simple good and cheap fuel pump a Ford fuel pump used from 86-91 works well. The part numbers it can be looked up on are:

AIRTEX REF # E2000

AC DELCO REF # EP286

CARTER REF # P74028

BOSCH REF # 69100

I used one on our formula car last year at WSU. Worked better than any more expensive aftermarket pump that we've used in previous years. I was just hesitant to do the swap because I didn't want to swap tunnel fuel lines.

Tangerine Racing has stainless steel fuel lines that are bent to fit, when I was talking to Chris he said he always tries to have a set in stock.

Ian Stott
Moncton
Canada

When I installed SS lines, I ran a die across the ends (about 1/2") to give the rubber hose something to bite into when I clamped it with a hose clamp .... no problems.