So... riddle me this...
Anyone know why none of the wiring diagrams for the 1975-1979 20r yotas do not have the wiring information for the electric fuel pump???? I've tried old and new chiltons, p/u and car, autozone online(alldata)... and the results... nothing.
So... the question persists...
Does anyone have a fuel pump wiring diagram?
If not, does anyone have any idea...
How this fuel pump system works?
Where the fuel relay is?
How the oil sender unit is wired in?
Where the oil sender unit is located?
What are the colors of all these wires?
How is the fuel pump resistor wired in?
Why does it have the resistor? To slow down the pump?
If it runs 100% of the time when the key is on, or is there some RPM/other shut-off switch?
So as you could probably tell I am having a problem with my fuel pump. I am the recent recipient of a 1975 Chinook camper which came with a completely none operational fuel pump. I've been trying to diagnose if its an electrical problem or mechanical, but there is no information about the circuit.
So far I have...
Measured voltage at the fuel pump connector -- 0v one side and a very erratic reading on the other
Put 12v directly to the pump -- nothing happened
I just dropped the fuel tank last night, but it began to rain and I was unable to perform any more testing.
Also it looks like there is a second external fuel pump 'T'ed into to the air vent with a plugged piece of rubber gas line on the other side of the device. Is this a normal set up to feed from a second fuel tank?
I'm gonna do a write up about this fuel pump if I figure it out, otherwise I guess I'll write up whatever workaround I come up with.
