Hi guys, I have a 72 240z, I have a carter 2-4 pound pump installed and ready to go at the back of the car. but I've run into a hitch.

When I try to close the circuit with an inline fuse (left of the fuse box, green/black wires that were taped to the harness with blue tape) it blows the fuse when i turn the ignition on.

The pump works fine when wired direct to power. so I have no idea what is going on.

When i check the plug that was secured with blue tape with a volt meter, it read's 12.2 volts. as I understand it, this should not be a grounded plug, it is supposed to carry power from the black wire to the green wire with a fuse.

Am i missing something here? my car wont go till i get this figured out!

Well I just ran my own wire from the black/white wire on that plug to the positive on the fuel pump, it's working now.

Only explanation i can think of is that the green wire going to the rear pump wiring was shorted somewhere.

What is the fuse rating that blows?

Sounds like a short in the OEM wiring that you're using. Here's how I wired up the electric pump in my '72...

Dave's 1972 Datsun 240z: Electric Fuel Pump Installation

thanks, i ended up bypassing the stock green wire from under the console and running my own from the black/white wire. on the plug.