Suburban Fuel Pump (for a second time)

[Donald]

I just finished replacing the fuel pump on my 1993 Suburban (for the second time). Its in the tank and not that easy. The real pain is that this pump only lasted 12 months and 1500 miles. Good news is that its covered under a NAPA warranty. Only had to buy a strainer and new locking ring.
The first time I did it I had to buy the entire fuel gauge sender part as the gas lines were rusty and snapped and that
was close to $200, the pump is only $40.

One thing I did realize is that the ground wire connection for the pump is merely screwed into the rusty chassis. The ground for the sender goes back with the wiring harness.

The old pump measured 22 ohms and the new one 6. The old pump when removed and connected to a battery acted like it was jammed. It was trying to turn but could not. The strainer was 100% intact so no junk from the tank should had gotten into the pump.

I also wonder if some of the time when people have a fuel pump failure in a Suburban, that its really a bad ground connection. You need to unscrew the ground connection to get things apart and pull out the tank. So by virtue of replacing the fuel pump, you will screw the ground connection back in.

I wire brushed the ground wire connector, and the screw and put some dielectric grease on both.

I wonder if the actual ground (for the pump) comes from the ground connector touching the rusty chassis or from the ground connector touching the screw head and the thread of the screw is in contact with the chassis. I did not wire brush the chassis.

 

[toocrazy2yoo]

I believe it's through the screw, especially when you're talking painted/coated surfaces..

 

[9c1]

It's probably too late now -- but one can never have too many good grounds. An extra ground wire of good diameter to a clean, firm chassis ground might help. It certainly would not hurt.

Sometimes for economic reasons manufacturers will not provide adequate wire connections given the deterioration that occurs to electrical connections over time. Everything is fine when the vehicle is new and connections are clean, but time and the salt used in the winter on northern roads deteriorates the electrical connections to the point that function becomes marginal.

 

[Jim 5]

That's a good tip. Thanks for that.

GM full-size owners are always hoping not to hear that loud pre-death fuel pump whine. The more we know about the problem and its solution the better.