Fuel pump isn't priming

[jamie88]

Hi guys, my fuel pump isn't priming meaning the old girl wouldn't start this morning! Before I look into replacing the pump, other than the relay is there anything else I should be looking out for? Thanks

 

[jamie88]

Think I may have found the problem. Corroded wire.

 

[Jamesv6]

Look for corroded wires.

 

[jamie88]

Haha yes I asked for that. Thought I'd answer my own question in case anyone searches for the same issue.

 

[DaveL485]

And was that the issue?

I thought shit like this was sorted out in the 80's *shakes head* reminds me of the crumbling connectors in my old R9

 

[jamie88]

Not sure just yet. I have a mate landing down with a soldering iron after work. Fingers crossed as I'm due an easy fix for once!! It seems that the fuse box cover has been rubbing on it for some time now.

 

[DaveL485]

It's a red wire, indicating it's a permanent live feed (yellow is ign live), so it could well be the direct feed to pin 3 of the fuel relay. The relay is fed from a live feed to pin 1 and then pin 2 exits to the ECU where the ECU controls a switched earth to activate the relay. Pin 4 will exit the relay and go to the pump + terminal, then the pump - terminal will exit to earth.

If fixing that wire doesnt work:
Pull the relay and see if you have +12v at pin 1 to earth when the pump is supposed to prime. The relay should click on and off when this happens anyway.
See if you have +12v permanent from pin 3 to earth...if so bridge pins 3 & 4 to see if the pump fires. It should. If not continuity test the pin 4>Pump+ wire, and check the pump- to earth. If theyre OK, test the pump itself independantly.
If the relay fires, and the pump tested OK with bridging see if you have 12v at pin 4 out with the relay plugged in.

 

[jamie88]

Nice one Dave appreciated!