71 Wiring for the fuel pump does not work.

[Dave]

I just installed a electric fuel pump in my 71 and used what they

say is factory wiring for the pump. The wires I attached to had

bullet connectors, were at the tank sender and taped to the

harness with blue tape. In doing a search I found reference to

blue taped wiring near the passengar side vent (JTR Book) and

some blue taped wiring behind the radio. I found both of these

sites but they don't run the pump when powered up. There is

not a battery in the car at this time and what I did was to

power the two connector sites up in hopes the pump would

run. Do both wires from the pump +/- end up in the dash

area or is the - grounded to the car someplace? Did I miss

something along the way? I have a filter before the pump

and another under the hood and what I want to do is run

the pump for several hours pumping Kerosene out and back

into the tank. The reason I am doing this is the car has set

for several years with out running. The pump and filters are

permanent and what I am using for the V8 conversion.

[Guest 305240]

Whenever I come across wires like that. I disconnect the battery and run a continuity test. Sometimes I get lucky. If it's there, it has to start from somewhere. I'll check my 73 FSM.

[Dave]

Whenever I come across wires like that. I disconnect the battery and run a continuity test. Sometimes I get lucky. If it's there, it has to start from somewhere. I'll check my 73 FSM.

 

I do have it half solved, the + wire from the pump ends up at the

connector behind the radio. The - wire at the pump is attached to

the chassis at some point. So by putting + power to the connector

behind the radio and the - attached to the chassis the fuel pump

does run. The connector behind the radio is a T connector with one

of the wires going to the pump the other wire is not the - for the

pump. Just where does the other wire go? I have a 71 FSM and

can't find any reference to the wiring that appears to be there for

the dealer installed electric fuel pump. If there is a relay they used

for the pump where did it go? what about the fuse? I can easly put

one in but if its there or a provision for one I would just as soon use

it.

[Guest 305240]

Here, try this out. I use altantic Zs tech pages quite often. Hope it helps.

 

http://www.atlanticz.ca/zclub/techtips/

 

scroll down to electrical and it gives wiring diagrams for just about every Z.

[Guest 305240]

Sorry, forgot to tell you, in the JTR book, it talkes about the wires you want to know about and what to do with them.

[Dave]

Sorry, forgot to tell you, in the JTR book, it talkes about the wires you want to know about and what to do with them.

I saw the reference to the wiring in the JTR book. But they said that the

wires were on the passenger side up by the air vent. The actual wire

that goes to the Electric fuel pump is behind the radio and in a T connector.

With no battery in the car but using a 12V power source with the + going

to the Green wire in the T connector and the - grounded the pump runs.

What I am trying to figure out is what does the other wire in the T connector

do? Is that the + power for the pump? and is there a fuse some place?

[Guest 305240]

Dave, I'm stumped here as my 73 FSM shows a green wire at the fuel pump going into the body harness. But, the body wiring scymatic doesn't show it. It did show a yellow wire going to the gauge and the radio. It must be the difference in the years as to what color went to what.

 

I'm guessing here. Would the other wire on the T perhaps go to the solinoid (or the start wire on the ign switch) to shoot juice to the pump while you are starting the engine? Then when the engine starts, the power to that wire is shut off and the other wire takes over to supply power? If it were me, that's the way I would wire it. I would also connect an oil pressure shut off switch into the system. This is the way I'm wiring my 260. Good old street rod style. As always, run it thru a fuse and a relay. This way you will know how it is set up and what to look for if something goes wrong.