240z Electric Fuel Pump Installation

[beandip]

I did this conversion in 2002 and have been using a electric pump from a RX-7 non injected car. Have never had any issues with vapor lock or any problem for that matter. I eliminated the mechanical pump, they act like a heat sink, and block off the opening. I have since changed engines to a F-54 with a P-79 head with cam and headers. No heat shield other that factory and again no problems. I used a simple tee into the block much smaller than the one pictured , attached the pressure switch to the side opening and the sending unit on the other. Looking at the area you cannot even see any difference from stock. I simply ran a couple of wires fron the pressure switch , right to the green wire comming from the pump on the passenger side . Cut the wire and connectec my new wires in line. This power sorce is fuesed , factory, with a inline 20 amp fuse between my splice and the power sorce. I can see no need for a relay, The pressure switch I use closes when the oil pressure reaches 7 psi. then the pump is activated. If you ever run out of gas, simply use a modern fuze with two male spade connecters , un plug your wires and bridge them with the fuze . Turn the key and fill the float bowls. I have had to do this only once. Even after winter there is enough gas in the carbs to start the engine. But if not I use the fuze. This makes it a simple and clean uncomplicated modificaton. Just take your oil sending unit with you to your parts store , tell the counter guy what you want to do so you will be buying the correct threded parts. This is about a $10.00 conversion . The RX pump is quiet too. $15.00 at the local u-pull-it. they make 4 1/2 psi. I cecked wtin ztherapy when I did this and Steve told me the limit pressure is 5 psi.

Hope this is helpful. All the best. Gary

Edited February 18, 2013 by beandip

[yuh]

Thanks for the instructions!

Where did you buy your brass T connectors?

[Jarvo2]

I ended up bringing my oil pressure sensor to Menards (hardware store, similar to Home Depot) and then did some trial and error in the brass plumbing section. I believe it was 1/4". Don't forget you'll also need a male-male straight pipe to get the "T" into the block. Looking back, the oil pressure switch was a little bit of overkill, but I am aiming for safety and drive-ability. I've heard of some people pulling power from the yellow alternator wire to power a relay (avoid the need for the multi-function oil pressure switch).

[malibud]

where did you mount the inertial switch and is needed ? I have never used one will cut power if you hit some railroad track hard ?

thanks for the write up going to follow your directions on my build .

[Jarvo2]

I decided not to install an inertia switch as I'm going to rely on the oil pressure gauge to cut the fuel pump off if the engine stops. From what I've heard, you can easily find a used one at a wrecking yard, or purchase one from RockAuto. It needs to be in a place that it can be reset, although I don't think speedbumps/railroad tracks would trigger it to flip unless you pull a Dukes of Hazzard jump.

[grannyknot]

ford inertia switch | eBay

This is one of the best inertia switches made, inexpensive and rock solid quality.

[malibud]

i think i will skip it too feel better relying on theol pressure switch . thanks interesting though

[Jarvo2]

You can always put in an on/off switch in lieu of the inertia switch, which would then act as a hidden fuel cut off switch....good luck getting the car started with it turned off!!

[formula c's 240z]

hi, im wondering how do u regulate your fuel?? bcus doesnt the fuel need to be regulated or it will overflow the carb?

please, give me a text for faster response. (209)-947-7595

[Jarvo2]

The airtex pump I used only produces 4-6 PSI which is fine for the SU's. If you get a higher pressure pump then you'll need to put a regulator in somewhere between the fuel filter and the hard fuel line in the engine bay. I haven't had any issues with my low-PSI pump.

[HuD 91gt]

Will using the oil pressure switch cause the engine to crank a few more times (To build pressure) before it starts?  Or will the fuel in the fuel bowls take care of that?

 

 

I'm just curious as every car i've dealt with, as soon as you turn on the ignition you can hear the fuel pump run right away.   Look's like I have to do this conversion as my N47 head does not have a mechanical pump cutout.

[Jarvo2]

The switch I had bypassed the oil pressure when it got power from the starter.  Check out the schematic that I drew.  There is a switched power, Starer Power, and output on that switch.