We have an old '88 1 ton dump that's a snow plow truck and you know the salt/corrosion deal. The other day the stock in-line fuel pump on the frame retired and a NAPA one replaced it. Now I am noticing the pump runs all of the time and fuel mileage dropped, and it runs like ____. Sometimes the pump won't run when you first turn the key on, soI have been monkeying around with the relays and sometimes the pumps runs and sometimes not. I've noticed someone put an in-line fuse with a jumper wire on one of the relays and one of the wires on the brown plug is loose.
I'm wonder if I should or could by-pass the whole mess and run a direct line with a toggle switch and fuse directly to the pump?
I would greatly appreciate any suggestions, help or advice and Thanks in advance.

 

How about wiring a hot wire and switch direct to the in line pump on the rail?