elec. fuel pump wiring

[narfire]

Getting motivated to finish off a 72 I've been mucking with for a couple of years.
For whatever the reason I've gone to an electric fuel pump mounted next to the fuel tank. I've grounded the black nearby and have run the red wire up and now underneith the dash. I have a relay and am wanting to wire the pump somehow in conjunction to the oil pressure sending unit so in case of accident and the engine stops and ignition is still on, the pump will stop.
The electrical is at the top of my weak point list.
Anyone done this and could shed some light as to what if any connections to the ignition, relay, and oil sending unit I have to make this work.
One can PM at work here okcustomcut@telus.net if someone wants to take this on
Thanks people
Chris

[westy64]

Getting motivated to finish off a 72 I've been mucking with for a couple of years.
For whatever the reason I've gone to an electric fuel pump mounted next to the fuel tank. I've grounded the black nearby and have run the red wire up and now underneith the dash. I have a relay and am wanting to wire the pump somehow in conjunction to the oil pressure sending unit so in case of accident and the engine stops and ignition is still on, the pump will stop.
The electrical is at the top of my weak point list.
Anyone done this and could shed some light as to what if any connections to the ignition, relay, and oil sending unit I have to make this work.
One can PM at work here okcustomcut@telus.net if someone wants to take this on
Thanks people
Chris

Chris,

I am in the same process on my 76, but I am not sure of the way it works.
far from being an expert, and still need a last help on this but here is my understanding.

I guess you know these diagrams :

http://www.globallistics.com/spidersweb ... emes/7.jpg

fuel pump relay is marked 128/3 on the diagram, and the fuel pump is down the page (left), number 120.
fuel pump relay is a normally closed relay.

it was normally wired with 128/2, (ignition relay), but you can do without.

Pink (hot after ignition) is to be plugged on 30 and 85, and grey on 87b (powers the pump as long as the relay is closed)
Grey / yellow on 86, is coming from the pressure switch sender.
When no oil pressure, signal on this wire is a ground (can anybody confirm ?) , and then the relay coil will open the "normally closed" circuit and wire 87b (and then the pump) is no more powered.

How does the engine first start, then ?
I guess this is why the pump is also powered by the grey/black wire from the ignition (plug 15).

Anyway, it make starting more complex when the carb bowl is empty.

Hope this help.





I am in the same process on my 76, but I am not sure of the way it works.

[narfire]

Thanks for the info. I'll print this off when at work later.
I have Brad's diagrams printed off for the 72. THANKS BRAD!!! and will attempt something today.
Kinda fun getting back into fiddling with these cars. Might have it sorted by the weekend and could try and start the thing

[narfire]

Ok, also looked in the back of the Haynes 1968-1978 manual (page 207,208,209) and they have schematics for a coupe UK model with electric fuel pump. I think I might be able to make some sence of those and do something similar.
I'll have a fire extinguisher ready
Chris

[courtenay]

Good luck, Chris. Be nice to the '72 on Fathers Day this year - if it's not raining, again, of course.

[donm]

Instead of using a relay set up, the other option to make sure the pump stops in the event of an accident is to place an inertia switch in series with your electric pump. Do a search for "inertia switch" to read all about it.

[westy64]

Here is a link to a post on inertia switch

http://www.tr-register.co.uk/forums/ind ... ia-switch/

[narfire]

Cool. Thanks for the info. I'll look into it tomorrow. I think I have the relay thing sorted but with the butt conectors and shrink wrap, I hope I have it right. The inertia switch looks way simpler.

[nibbes123]

Chris you can remove it from a ford Windstar harness and all and hook it up in the trunk of your car right side near where your jack goes on the solid part. Did this on a 78 spider I had converted to electric fuel pump.
Nick

[westy64]

Here is the inertia contactor (switch ?) I bought yesterday at the dismantler ( 10 $ ).
Comes from a Peugeot or Renault (this model is used on both).
My request was "a small one" and they did not come to me with a Fiat (too bad).





Still have to define the best place to fix it, and how to wire it, as it seems that the wires are very thin, and I don't know its cut power. I guess it originally cuts a relay power, and not directly the pump.
Any advice on this ?

[rodman]

Here is the one I bought at the dismantler ( 10 $ ).
Comes from a Peugeot or Renault (this model is used on both).
My request was "a small one" and they did not come to me with a Fiat (too bad).





Still have to define the best place to fix it, and how to wire it, as it seems that the wires are very thin, and I don't know its cut power. I guess it originally cuts a relay power, and not directly the pump.
Any advice on this ?

Wire in-between the negative it has no choice to cut the power from the pump once activated. Only two wires coming into it?? One in and one out.

[RRoller123]

It is generally felt that the best place to mount it is very rigidly on the frame of the car in the trunk near the tank.

[baltobernie]

Here's a USA source: http://www.summitracing.com/parts/SUM-890145/ I think this is identical to the Ford switch that was mounted in the trunk of every Taurus made.

As others have mentioned, it must be rigidly mounted vertically; button up, wiring down. The inertia switch is on the right of this bracket



This switch has a N/O contact that can be wired to a warning lamp indicating a tripped state, but I think the button pops up, too.