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fuel pump not pumping

I had thought about the new wire, it's OK with me. I ran the Crusader Diagnosis which indicates "a short to ground in the battery feed circuit to the fuel pump relay." I'll just have to find the battery feed connection.
I will try the jumper first.
I do appreciate your assistance in this, it helps clear the fog!
 
if you measured < one ohm on the pump side of the relay, the description is a bit misleading....its the 'battery feed' that the relay provides to the pumps....
 
Pin 30 is the fused feed from the battery (PNK/BLK)
Pin 86 powers the coil, and should get battery voltage with the ignition switch in RUN (PNK)
Pin 85 goes to ECU which grounds it, internally, to close the relay (turn on the pumps) (GRY)
Pin 87 provides battery voltage to the pumps when the relay is closed. (DK GRN)

all of the details are in the MEFI-4 manual, in multiple places - diagnostic procedure A-5 was the first place my search found it.

for the wire colors, the first one is the main jacket color and the second one is the tracer or stripe). Based on what you've shared, the 'short' appears to be in the GRY wire, between the relay and the pumps - that's the candidate for replacement.
 
Thank you. I traced the wires so I should be able to complete this. I do understand wire colors, my copy page A-5 shows 85 as DK GRN and 87 as GRY only 2 of which match the physical relay.
I really appreciate your help as I said this is 90% new to me, no mechanic here familiar with this, but good with outboards.
 
you are correcton the colors for those two - i interchanged them on my note sheet....sorry about that.

Let us know how it pans out...
 
Don't worry, the relay on the engine had 2 pink and 2 grey wires, no stripes. Confused me. I'm anxious to get to it, holiday weekend, we'll see.
 
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Mark, I took your advice and looked over the harness for some aberration, tracing the pump wires where they joined the harness they were separated from the main harness, the only spot like this in the entire harness. Even though nothing appeared visible I replaced the fuse, reinserted the relay and it fired right up. So I replaced the wires into the loom, taped it all up carefully keeping it away from the manifold and it runs fine. I'll test it out this weekend, hoping for the best.
Again, thanks for your assistance, it was a great help. Hope it is really fixed.
 
Mark, just to catch up. We noticed a small break in the wire going to the fuse in question with a little green corrosion, cut out the corrosion installed a butt splice and has worked well since. It seemed too insignificant to be the problem but it apparently was enough. Thanks for your help.
 
No problem....that's what we are all here for...

My guess is it acted up again....and replacing the fuse wiggled the wire enough (at the break) to pass enough current for the pump to run....and then you found the infamous "green spot"....

Hope the butt connector was shrink wrapped (or added afterwards)....and you noted the root cause in your log book....its amazing how frequently 'recurrences' happen...
 
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