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Tired of the Fuel Pump screaming at me....

Discussion in '308/328' started by TurtleFarmer, Jan 14, 2021.

  1. TurtleFarmer

    TurtleFarmer Karting

    Jan 13, 2020
    162
    Full Name:
    Jason S
    Over the past six months, the fuel pump has gotten louder in my '79 308. A very annoying high pitched whine that is quite audible from the cabin--even over the engine. After a 3-5 minutes, the pitch note changes to something that is a lot less annoying.

    It's the original pump--and from both my mechanic and all you wonderful fchat folks, it sounds like this is a common failure point.

    So I replaced it this week with a new Hardi 18812 pump.

    Also the PO had gotten rid of the 3-way valve that enables a bypass in the event of a severed line and replaced with a straight 3-way hose fitting. In other words, the pump was not only pressurizing the carb feed lines, but also bypassing back to the input of the pump (yes, this is a bad setup). I'd thought that change of pitch might've been the pump struggling to build pressure b/c of that bypass and then finally being successful as the system reached an equilibrium.

    So, before replacing, I also took the opportunity to record the pump sound both with and without the bypass (using a hose clamp). Turns out it didn't make a difference--that pump was just loud and as it warmed up, it simply changed it's note.

    So after replacing the pump AND removing the bypass entirely (set up like the EU-spec cars), it's so so much better. I can still hear the pump lightly before the engine is started, and then nevermore.

    Will post a couple videos of the before and after.
     
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  3. TurtleFarmer

    TurtleFarmer Karting

    Jan 13, 2020
    162
    Full Name:
    Jason S
    Arg...video files are too large to post. Lemme put 'em onto a share drive somewhere...
     
  4. TurtleFarmer

    TurtleFarmer Karting

    Jan 13, 2020
    162
    Full Name:
    Jason S
    Cut the video's down. Here's the first one (original pump)
     

    Attached Files:

  5. TurtleFarmer

    TurtleFarmer Karting

    Jan 13, 2020
    162
    Full Name:
    Jason S
    And the second one (Hardi pump).
     

    Attached Files:

  6. Milkshaker0007

    Milkshaker0007 Formula Junior

    Sep 22, 2012
    336
    Midlands,uk
    Full Name:
    Paul
    sounds so much better, nice job
     
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  8. ragtop1

    ragtop1 F1 Rookie
    Silver Subscribed

    Nov 11, 2006
    2,959
    Ontario, Canada
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    Larry Warren
    Mine sounds like your old one in really cold weather until it warms up, then becomes quiet. It's always been like that.
    Good job on your fix .
     
  9. JohnInItaly

    JohnInItaly Karting

    Feb 5, 2019
    65
    Santa Cruz, California
    Full Name:
    John McCoy
    When I changed to Birdman fuse blocks in my 1974 308GT4 and turned on the key, my fuel pump was very quiet, which was unexpected.
     
  10. TurtleFarmer

    TurtleFarmer Karting

    Jan 13, 2020
    162
    Full Name:
    Jason S
    The new fuse block should almost certainly providing better voltage to the pump than the stock block, so it's not surprising that the "note" of the pump might change. Usually, I'd expect a higher pitch (more voltage = higher motor speed) -- but quieter? That is unexpected.

    I assume it's still working and you didn't just forget to connect the wire for the fuel pump :) If that were the case, then a quieter pump would be expected....
     
  11. JohnInItaly

    JohnInItaly Karting

    Feb 5, 2019
    65
    Santa Cruz, California
    Full Name:
    John McCoy
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  13. Nuvolari

    Nuvolari F1 Veteran
    Sponsor Owner

    Sep 3, 2002
    5,587
    Toronto / SoCal
    Full Name:
    Rob C.
    The Hardi pump makes a different sound to the original. The original pump makes a whirring sound (when working correctly) while the Hardi is more of a soft thumping sound and is almost identical in sound to the Bendix pumps fitted in Dino and Daytona models. All of this is pretty academic as soon as the engine starts as the motor sound drowns out any note from the pump.
     
  14. ragtop1

    ragtop1 F1 Rookie
    Silver Subscribed

    Nov 11, 2006
    2,959
    Ontario, Canada
    Full Name:
    Larry Warren
    I was under the impression that that the plastic covers wouldn't fit over the birdman retrofit. Was I misinformed?
     
  15. TurtleFarmer

    TurtleFarmer Karting

    Jan 13, 2020
    162
    Full Name:
    Jason S
    They don't. You'll note in John's photo that the covers are shorter than the fuse block (one side bisects the outer fuse) and that they aren't seated onto the block itself. I'm guessing John's done some creative work to get them to stay in place...
     
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  16. Brian Harper

    Brian Harper F1 Rookie
    Owner

    Feb 17, 2006
    3,825
    San Jose area
    Full Name:
    Brian Harper
    My car is in that photo also! About 17 yellow pixels way in the background...
     
  17. JohnInItaly

    JohnInItaly Karting

    Feb 5, 2019
    65
    Santa Cruz, California
    Full Name:
    John McCoy
    I was officially sanctioned on Fleabay for using the word VELCRO to describe the closures on genuine Ducati tool bags, and so I will reveal my secret to making original 308 fuse block covers fit the fabulous Birdman fuse blocks as being "hook and loop" fastening strips, purchased at Home Depot (which might be genuine Velcro products, which I can no longer personally endorse). :)
     
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  18. JohnInItaly

    JohnInItaly Karting

    Feb 5, 2019
    65
    Santa Cruz, California
    Full Name:
    John McCoy
    I hope to see you there this year, as 2020 entries roll over to 2021, and I entered both the 308 GT4 and a newer Ferrari.
     
  19. JohnInItaly

    JohnInItaly Karting

    Feb 5, 2019
    65
    Santa Cruz, California
    Full Name:
    John McCoy
    Correct about hearing the pump only before the engine starts. After my new fuse blocks, I sat there waiting for the usual screaming fuel pump to start, but eventually heard just a gentile hum. I have owned the car for thirty years and suspect that the pump is original, despite our lousy California ethanol gasoline. It sounds happier now, and no complaints from me.
     

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