1. Registration trouble? Please use the "Contact Us" link at the bottom right corner of the page and your issue will be resolved.
    Dismiss Notice

Chevy 4.3 Fuel Pump Noise

Discussion in 'Flat Fender Tech' started by 47v6, Apr 15, 2022.

  1. Apr 15, 2022
    47v6

    47v6 junk wrecker! 2023 Sponsor 2022 Sponsor

    USA
    Joined:
    Oct 25, 2006
    Messages:
    5,798
    The fuel pump for my 4.3 is the stock style one that came with my Astro van. I built an in tank holder and it works fine.

    it makes a lot of noise though and periodically it sounds like it’s straining, when that noise occurs the volt meter drops to about 12.5 for about 1-2 seconds, so it’s pulling more power at that moment.

    It’s not related to the level of fuel in the tank. Does it full or less than full.

    Is the fuel pump beginning to fail? It’s not new. It’s also not original.
     
  2. Apr 15, 2022
    Jw60

    Jw60 Sitting up n buckled down. 2024 Sponsor 2023 Sponsor 2022 Sponsor

    Sedalia MO.
    Joined:
    Apr 8, 2008
    Messages:
    4,717
    How clean is the inside of the fuel tank?
     
  3. Apr 15, 2022
    47v6

    47v6 junk wrecker! 2023 Sponsor 2022 Sponsor

    USA
    Joined:
    Oct 25, 2006
    Messages:
    5,798
    As clean as it can be. I had to cut a big hole in it to plumb in the sump, so I had to do a good job cleaning it all out really well.
     
    Jw60 likes this.
  4. Apr 15, 2022
    Rich M.

    Rich M. Shoe salesman 2024 Sponsor 2023 Sponsor 2022 Sponsor

    Maryland
    Joined:
    Mar 23, 2008
    Messages:
    2,169
    Spare for the parts bag, do you have a pressure gauge?
     
    Lockman likes this.
  5. Apr 16, 2022
    45es

    45es Active Member 2024 Sponsor 2023 Sponsor 2022 Sponsor

    Naches, WA
    Joined:
    Mar 31, 2007
    Messages:
    1,103
    Your fuel pump is going to sound loud as compared to your other vehicles. It's one of the first things I also noticed when I built my setup. The pump is closer to you with nothing to attenuate the sound as apposed to your other vehicles. I did find that different brands are more quiet than others.

    Look more closely at both the fuel pump and the electrical system. Is the voltage dropping because of the fuel pump beginning to fail or is the pump straining because of the drop in voltage to the pump due to say for example, a faulty wire splice. It could be either. Did you use the fuel pump cartridge assembly from the van or something else?
     
    Lockman likes this.
  6. Apr 16, 2022
    47v6

    47v6 junk wrecker! 2023 Sponsor 2022 Sponsor

    USA
    Joined:
    Oct 25, 2006
    Messages:
    5,798
    I used the old fuel pump cartridge. It was not a GM unit, but a replacement as far as I know. I will check wiring and probably buy a new pump anyway.
     
    45es likes this.
  7. Apr 16, 2022
    scott milliner

    scott milliner Master Fabricator

    Seattle Wa.
    Joined:
    Dec 17, 2002
    Messages:
    2,361
    My fuel pump came from the S-10 I used. I installed a new pump when I put it in the under-seat tank. It's noticeable but not loud.
     
  8. Apr 16, 2022
    47v6

    47v6 junk wrecker! 2023 Sponsor 2022 Sponsor

    USA
    Joined:
    Oct 25, 2006
    Messages:
    5,798
    I have mine between the frame rails in the back with a 15 gallon tank. Its louder than the engine at idle
     
  9. Apr 16, 2022
    duffer

    duffer Rodent Power

    Bozeman, MT
    Joined:
    Sep 17, 2009
    Messages:
    4,460
    That does sound like its on its way out. Is it still putting out the required PSI? It would be revealing to see what the pressure does when the current draw goes up. If you have to pull the tank or box to replace the pump as in my GM pickups, It really doesn't make any scense to put a used pump back in if your time is worth anything. And why I stuck with an inline pump in my 3B that takes maybe 15 minutes to change out.
     
  10. Apr 16, 2022
    47v6

    47v6 junk wrecker! 2023 Sponsor 2022 Sponsor

    USA
    Joined:
    Oct 25, 2006
    Messages:
    5,798
    I believe its putting out the required PSI because it still runs. These need a minimum of 58 PSI to run at all and I have no issues so far. I put the old one in because at the time there were none to be had. Everyone was out of stock, pandemic or some excuse. Now I can get as many as I want..It also seems that this is the pump everyone uses and the aftermarket ones aren't recommended.
     
New Posts