Fuel pump relocation wiring question, the wiring is done I have a new question! Options

[scott_in_nh]

So a couple of weeks ago I decided it was time to take care of a few projects on my 74 2.0 D-jet.

A PO moved the 3 port fuel pump up front under the steering rack, but never replaced the plastic fuel lines.

The fuel pump works ok, but is noisy and doesn’t hold pressure when I shut the car off.

The wiring for it was also cobbled – two wires were run through the tunnel and plugged into the original fuel pump plug, but apparently the positive wire failed so another wire was run from the relay board through the interior and to the pump.

It was still grounded through the tunnel wire and original pump harness.

I installed Tangerine SS fuel lines and replaced all other rubber lines I hadn’t already replaced and now I am installing a 2 port fuel pump and filter in the same location.

The layout proved quite challenging, but I think I have a good solution.

My question is can’t I just run the positive wire through the tunnel and ground the fuel pump in front?

I did a search and some refer to running “wires” (plural) through the tunnel and some talk about running “a wire”.

I just want to make sure I’m not overlooking something…..

[gothspeed]

Scott, thanks for following up on your progress! I have finally mounted my fuel pump under the steering rack. So far I think I will be running 12v power to the pump from the battery using a relay. The relay will in turn be triggered by the factory harness wires for the orignal fuel pump.

Since I am going with carbs for now, I will be going with the extra ground from the relay panel in the engine compartment.

Did you run fuel pump power with the 'key only' or did you also include an oil pressure switch to control power to the pump? If you included an oil switch in the circuit, how was it done?

I am under the impression the the swtich is open under pressure, which is the opposite of what one would need to complete the circuit.

[scott_in_nh]

Scott, thanks for following up on your progress! I have finally mounted my fuel pump under the steering rack. So far I think I will be running 12v power to the pump from the battery using a relay. The relay will in turn be triggered by the factory harness wires for the orignal fuel pump.

Since I am going with carbs for now, I will be going with the extra ground from the relay panel in the engine compartment.

Did you run fuel pump power with the 'key only' or did you also include an oil pressure switch to control power to the pump? If you included an oil switch in the circuit, how was it done?

I am under the impression the the swtich is open under pressure, which is the opposite of what one would need to complete the circuit.

I am running D-jet so I am wired to the fuel pump terminal on the relay board.

[gothspeed]

It's been a long time, but the switch has contacts for NO and NC. The NC powers the pump while turning the starter. Once the engine fires and you have oil pressure, the NC opens and the NO closes to provide continuous power to the pump.

That is awesome ....... I was wondering about power to the pump while the engine was turning .......... I thought if one used the oil pressure only, one might be cranking for a while until oil pressure built up ........... so power to the pump while cranking makes perfect sense ....... (IMG:style_emoticons/default/smile.gif)

Just to be clear ........... we are talking about the ignition switch that has the NC and NO options correct?

I am running D-jet so I am wired to the fuel pump terminal on the relay board.

OK thanks! I was working on the fuel lines this morning ..... (IMG:style_emoticons/default/smile.gif)

[SLITS]

Just to be clear ........... we are talking about the ignition switch that has the NC and NO options correct?

I was describing an aftermarket fuel cutoff switch.