Fuel pump woes

[RayW]

Just thought I’d share my recent fuel pump woes in case it could help anyone. I recently had to replace two old failing fuel pumps— one on my 73 Commando 304 and one on my 70 Wagoneer 350 Buick. First, I ordered a Delphi fuel pump for the 304. After start up, engine sounded like it had a horrific valve tap. It was the fuel pump— rocker arm just rattled up and down. Ordered a Carter. Installed the Carter only to find the outlet fitting barely threaded, not even enough threads to tighten the flare nut. Received replacement Carter. Ran fine for a minute, then started idling roughly with fuel coming out of the MC 2100 vents (rebuilt carb BTW). Put my vacuum/fuel pressure gauge on the pump and 10 lbs of pressure (maxed out the gauge). Returned the Carter and ordered a Crown. Same thing— flooding, etc. Fuel pressure gauge again was pegged at 10 psi. Tried a regulator, but with no place for the excess fuel to go, gas just leaked out around the fuel pump bowl where it was crimped to the body of the pump. Fortunately Carl Walck had an old nos Carter pump from probably the 80’s made in Canada. Installed the old Carter and it runs beautifully. 4.5 lbs of pressure from the pump, smooth idle, no flooding or running rich— car’s been running great. Now for the Wagoneer. New Carter pump, same rough idle, flooding, etc. This Carter is putting out 9 lbs of pressure. TSM calls for no more than 5.5 lbs. The Wagoneer fuel pump has a return, so installing a regulator set to 5.5 lbs has been working fine and the Wagoneer has been running great. That’s 5 new pumps, and not one performing to the application’s OE specs. Are there any good, new fuel pumps out there?

[6erWebb]

I went through similar, the mechanical pumps I tried wouldn’t fit under my power steering bracket. When I found one that fit okay, I started having fuel vaporization issues. I decided to switch to the ol Delphi in line electric low pressure fuel pump. With that I had ok results for a bit but it only lasted about 4000 miles. I recently finished up an install of the universal in tank pump from tanks inc:

https://www.tanksinc.com/index.cfm/page ... /prd84.htm

You’ll need a regulator too, but I went a step further and rerouted my new fuel lines outside the frame away from anything hot. Regulator keeps the pressure at a constant 5.5, fuel stays cool, I love it!! Can’t speak highly enough.

[sierrablue]

I had a mechanical pump for 20 or 25k miles or so, and it gave up the ghost on me in early '23. Everything I read indicated that the replacement fuel pumps don't last as long and aren't very good quality; I also tried an electric Mr. Gasket pump, which lost its prime and also died randomly. I ultimately went with an electric pump from Carter. I need to get some bushings on it to make it shut up, and I may go to an in-tank if I go TBI.

The Carter has been loud but consistent so far (knock on wood). I would recommend it; it's a solid pump and you don't have to saw on the starter to get it to run. If you're looking at a restoration and want to keep it stockish, I understand though.

[ntsqd]

I've used the Walbro GSL395 on now two different vehicles. This is the inline (external) TBI pump rated for 20 PSI. I use a Holley by-passing 4.5-9 psi regulator* and set up a return line. I make the line from the regulator to the carb as short as possible. Set-up this way I've never had a vapor lock problem, even with summer fuel.

I've read people commenting that the Carter electric pump is loud. I assume that they're talking about the P4070 or one of it's derivatives. I've never experienced that, and I've used them on several different vehicles. I can assume that these people have never used a Holley Blue Pump. Those are loud.

*Just to be clear, Holley says that this input pressure is too high for this regulator. In 10's of thousands of miles I never had any problem with it, but it should be mentioned.

I use one of these oil pressure switches to control the fuel pump's relay. There are 3 terminals on it, one is power in, one is power to the pump, and the third is a start mode by-pass that runs the pump while starting the engine.