Hello everyone. I am new to the forum.
1985 Nissan 720 4X4 Z24 motor
I have a problem with my fuel pump that I cannot get a grip on. I know that the fuel pump has 2 sources of power. I will refer to them as "Fuse block" and "Battery".
The source from the Battery was unplugged when I got the truck. The reason is that when you plug it up the fuel pump comes on and the air mixer (don't know the proper name but you can hear it running in the front of the carburetor) in the carburetor comes on, this is with the truck tuned off and key out of the vehicle.
So the battery supply must remain unplugged.
That being said, the Fuse Block source runs the truck. It does not shut off. As long as the truck is turned on or cranked the fuel pump runs from this source. No time-out, it runs continuously. (Power from battery is unplugged)
I have replaced the oil sending unit, The relay beside the battery, and the fuel pump module beside the blower motor inside the cab on the passenger side, Checked alternator voltage, Have found no evidence of any kind jumper wire that someone has installed.
I would like to get this corrected because the air mixer in the carb. does not work. So until the truck warms up it runs too rich and causes to smoke a little.
Any help would be greatly appreciated.