Nissan fuel pump works- WHY

Discussion in 'Shop Talk' started by JV, Sep 15, 2004.

  1. JV

    JV Well-Known Member

    May 26, 2003
    Thanks for the good advice yesterday. So I spent the day getting the protective cover off, sometimes with the use of a hammer, and trying to figure out if the electricty worked. A tester I borrowed from my neighbor was different than I had seen in the past or described yesterday so I am still not sure If this morning there was power to the pump. I did buy the Chilton's book and spent some of the day trying to figure out the wiring, which had me real worried if it was something elecrical because it doesn't seem like it would be easy to fix. And towards the end of the day, when I was frustrated with my lack of progress and tried a different method to try the elecricity the pump made a noise. Now the truck starts and works just fine. So was it the hammer or all the wire jiggling? I wish I knew because now I'm quite nervous to drive anywhere. The pump is making a tick tick tick noise but I'm not sure if it always did that. Any ideas or a hypthesis?
  2. daeve

    daeve Well-Known Member

    Jan 24, 2003
    East Central Alabama
    Couple of possible reasons it started working. Most likely the brushes are worn out and the hammering and banging has caused the last bit of brush to make contact. I have heard a fairly quick ticking coming from motors and alternators when the brush was gone and the spring that used to be behind the brush is now making contact with the armature. The ticking could also be the pump its self and the hammering dislodged a piece of trash that was keeping it from being able to turn. Hard to say without taking it apart... If the truck had a hundred thousand or more on it I would go ahead and replace the pump.

    Fuel pumps are about the same as an alternator, at a hundred thousand if it ain't dead yet it is close. They are designed to last that long and then be replaced along with the rest of the car...

    Good luck!

  3. comfortablynumb

    comfortablynumb Well-Known Member

    Nov 18, 2003
    Dysfunction Junction, SW PA
    dont get to enjoy it I too have a nissan 85, and mine eats a fuel pump about once every 2 yrs or so.
    yes if you whack em they will start working again but will quit after a while.

    Go to nappa, get a universal pump, they carry 2, get the stronger one. it has to be where it is or it wont pump right.

    i thought it was wires and fuses too. mine is ticking away on its new pump now for about a year.

    I wouldnt open those sealed pumps.... they are like bic lighters, if they die, get a new one.
  4. Cabin Fever

    Cabin Fever Life NRA Member since 1976 Supporter

    May 10, 2002
    Between Crosslake and Emily Minnesota
    A while back the fuel pump in my pickup had "died" right in the middle of a parking lot. I took a hammer out and banged on the fuel tank (the pump was inside the tank) while my dw turned the starter key. Guess what, it started. A couple weeks later, the pump would not run....did the same hammer trick and it started. At any rate, I did this 3 or 4 times before no amount of banging with a hammer would get the pump moving....that's when I had a new one installed.

    What I'm saying is, "JV, you're livin' on borrowed time." Replace the pump. Dave is right, the brushes are just about gone.

    P.S. The hammer trick can also work on a "dead" starter motor.