Fuel issues continue...

[Uncle Gump]

On the inside frame rail just ahead of the right rear tire.

 

[bronco_d]

That can be a problem. High pressure pump is designed to push well enough... but it has very little suction. It will have a hard time pulling fuel from the tank below 1/2 tank.

If the low pressure in tank works properly... no issue. But if it doesn't work...

Test the low pressure pump...

This is exactly why I did my fuel system th I suggested.

Definitely looking like a better idea by the minute. I might have to rethink this. This is a lot of extra parts to worry about.

 

[tw205]

As uncle Gump said, converting it to a better setup will simplify the system. In 89 ( I think) they went with a high pressure in tank pump to a filter on frame rail then to fuel rail then returned to tank. Only 1 pump, no inline canister. Much simpler and easy to convert.

 

[JerryC]

Make sure you have the wires on correctly and that you are not running the pump(s) in the wrong direction.

You can do this with pumps not mounted to the BII.

 

[bronco_d]

Make sure you have the wires on correctly and that you are not running the pump(s) in the wrong direction.

You can do this with pumps not mounted to the BII.

Woohoo!! I have fuel!!! Still not sure if the pressure is enough but I have fuel. Oh.. but she still won't start but I think I'm a step closer.

 

[bronco_d]

Picked up a pressure gauge and i learned a couple more things today. 1. I have a leak on the return line. I'm starting to lose faith in these quick connect couplers. On the plus side i have fuel in the return line. 2.. if I jump the relay 3 to 4 I get 40 psi at the rail. If I just crank the engine I get just around 10. I put a multimeter on the red line going to the high pressure fuel pump and it didn't seem to give me any voltage when I cranked the engine but got roughly 10v with relay jumped. I'm going to double check my results but it would seem that the high pressure fuel pump is not getting power but the wire is at least good?

 

[bronco_d]

Should be a fuel canister between in tank pump and high pressure pump.

It may have been removed?

Those canisters keep a supply of fuel at the high pressure pump.

If it's gone and low pressure pump doesn't work... it's starving the high pressure pump.

Take the line off from the high pressure pump that goes back to the tank. Ensure low pressure pump sends fuel to the high pressure pump.

Not wanting to hijack anybody else's thread. But.. you posted this to Broncogirl.

"
So test tan/lt grn as follows.

Remove fuel pump relay.

Test light between B+ and tan/ lt grn wire.

Watch the light... turn key to ON position. Test light should illuminate for approx 2 or 3 seconds and go out.

Note... it will not illuminate again the key cycle until engine RPM goes above approx. 500 RPM. Starter alone will not crank the engine that fast."

If I do this my light turns on as soon as I plug the light in and stays on.. no key on. What does this mean?