Road King Fuel Pump Issue

Discussion in 'Electrical' started by FLHPI, Aug 18, 2012.

  1. FLHPI

    FLHPI Member

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    I have a 2000 Road King Police FLHPI.
    Problem I am having is with fuel pump. I turn the ignition and hear the pump whine. Hit the start button and it fires up. Ride it just a block or so and it dies. (engine dies but all lights etc are still on)

    When I switch the button to run I hear the fuel pump relay chatter and the fuel pump itself tries to whine, but never completes the full “whine cycle”. Eventually after repeated tries on the run switch the relay stops chattering completely and I get nothing.

    If I let the bike sit for an hour or so I can complete the whole scenario over again. Hit the run switch Fuel pump whines as normal, bike starts then dies after a short trip. Back to relay chattering.

    I have changed the fuel pump relay, battery voltages (appears) good, 12.6 at rest, 13.3 when running.

    I have checked wiring for nicks. No engine codes.

    Where should I look next? Appears fuel pump is working because the bike runs, but not for very long.

    Does appear to be a short, as it runs for a period of time.

    The "letting it sit" part is where I am stumped? Is it over heating issue? It never really runs long enough to get very hot.

    I have service manual and schematics, I have been stuck in the garage far to long and I am trying not to give up and take it in. Any help is appreciated.
     
  2. Bodeen

    Bodeen Well-Known Member Staff Member Moderator Contributor

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    Have you checked system voltage when the relay was/is chattering? Is the socket for the relay good and clean inside? If you could get a voltage at the relay on the coil side of the relay, it would tell the story.
    Of course you need to disconnect battery cables at both ends clean, and tighten, Same for grounds remove, clean tighten. Sure sounds like a vibration issue more than a heat issue.
     
  3. FLHPI

    FLHPI Member

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    I think I am going to check for Fuel Hose holes as decribed here:

    hdtalking.com/diagnostics_and_fuel_injection_related/979-engine_dies_and_runs_in_spurts.html

    I was holding off on opening the fuel tank for last, but I think it's time for at least an inspection. I do hear some noise inside the tank when the fuel pump primes, but It's hard to tell if its suppose to sound like that.
     
  4. xcavater

    xcavater Member

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    Sounds to me like the fuel pump itself is going. If you haven't had the fuel lines changed, now is the time to do it. Going into the fuel tank is easier than you think. The only difficult part is getting the fuel filter assembly to pivot. Search videos on YouTube there's many on how to do it. Replace the check valve/line assembly, fuel filter kit at the same time. You should be able to reuse all gaskets and screws.
     
  5. Webbtron

    Webbtron Banned

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    My 2000 RKC has the 3 wires for the fuel pump running from the seat/battery right under the tank....clearly labeled might be another pinch point.
     
  6. FLHPI

    FLHPI Member

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    I was able to get the pump assembly out of the tank, without too much trouble. I inspected the suppy line for known issue of rubbing holes. I can definetly see where it was rubing the tank however I do not think it has rubbed through yet. I tried blowing into the line and did not see a leak. I am hoping the pump itself can be replaced without replacing the whole assembly. It's priced at around $700. That is not a "Maybe I will try it" fix.
    I will replace the supply line, since I have the tank open. And I will check to see if the pump can be replaced by itself. I can handle a $100 "try it" but $700 is alot of money for me.
    As far as the pump itself is concerned does this make sense to anyone? The pump works fine for a short period of time, then quits. Attempts to try to restart would make the fuel pump relay stop,start, stutter, trying to get the pump to start and it can't.
    I know a chattering relay usually means low voltage, but It seems I got power.

    I also know now, I cannot realy perform any more testing until I get the tank put bak together.

    I have inspected those wires, Thanks. I have also checked almost every other wire on the bike. But as I get further into this, I am no longer suspecting a short. The problem has become so consistent and predictable. It starts, runs for awhile, then quits. Let it sit for awhile, and it repeats the whole process over again.
     
    Last edited by a moderator: Aug 19, 2012
  7. xcavater

    xcavater Member

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    Still think the pump itself is going and locking up. It's drawing too much current and causing the relay to kick out.. Run the pump while out of the tank, just put the pickup in a supply of fuel, plug the end of the pressure regulator. You should hear how healthy it is running on bench.
     
  8. Hoople

    Hoople Account Removed

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    I don't have the schematics in front of me but I am pretty sure the "fuel poump relay" is actually the system relay on that bike. Don't jump to conclusions. I believe that relay drives a bunch more than just a fuel pump. Try extracting DTC codes first using jumper wire method.

    What's a full "whine cycle" mean. How long is a normal complete whine cycle.

    There is no current control circuits on that year bike. The fuse was the only protection it has for current limiting.
     
  9. FLHPI

    FLHPI Member

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    I have a schematic showing a separate fuel pump relay. I have 3 relays under the seat. power relay, fuel pump relay and ecm power relay(system) and the two relays on the left side, starter and brake light.
    Normally when I hit the run switch I get a whine from the fuel pump that lasts 2-3 seconds and stops. After the bike dies and I try to restart the fuel pump only whines for about one second, then stops then whines again for one second and stops, and you can also hear the fuel pump relay click on and off in concert with the fuel pump. Eventually the sporatic fuel pumps stops completely. Then when I let it sit for at lest one hour, it will start again. I do not have any codes displayed.
     
  10. Hoople

    Hoople Account Removed

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    Ok regarding "fuel pump whine" time. I just wanted to hear your version.

    Until I can look at the schematics in the morning, your sure there is a dedicated relay that drives only the fuel pump? I know the schematic shows a relay "labeled" fuel pump relay but I thought it also supplied power to other devices. I am just working on memory without the wiring prints.

    Regarding the DTC codes. You actually performed the jumper wire test and you did not see any morse code flashing.