Fuel Gauge Dead - Sender replaced - What I found

Discussion in 'Parallel World (790/890)' started by windblown101, Apr 12, 2021.

  1. windblown101

    windblown101 Long timer Supporter

    Joined:
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    This has been my fuel gauge for the last several thousand miles.

    bike gauge.jpg


    I checked and had power to the fuel gauge sender. Removed the sender from the tank and the float was sliding normally inside the tube. I checked sender with an Ohm meter and was getting a range of 110 ohms to 10 ohms from full to empty. Unfortunately the repair manual doesn't provide what the expected Ohm range should be for the sender, so I ordered up a replacement.

    Finally got around to installing the new sender today and figured I'd outline the steps I took and what I found. First off, I had around a half tank of gas still so I dropped the bike onto it's side to let the gas flow to the fuel pump side then closed the transfer petcocks and picked it back up. This made for a lot less mess or having to drain the tank.

    bike down.jpg

    Ready to operate.
    bike ready.jpg

    I pulled the sender and started making comparisons: Both senders measured the same ohm range. Both floats seemed to slide easily inside the tube. I was starting to wonder if I was barking up the right tree replacing the sender.
    bike ohm.jpg


    Hating the idea that I had missed something I took the old sender apart.
    bike fg parts.jpg


    Dropped the float from the old sender into a container of gas. It sank like a rock. Problem found! Dang Italians...
    bike no float.jpg

    The float absorbed fuel and lost buoyancy. Can't blame this one on me!


    Got the new sender installed and have a working gauge again! :) A handy thing to have if I forget to set the ODO at a fill up or were to develop an unnoticed fuel leak while riding. Glad to have it back working again. I might let the old float dry out and do some reading on what I would safely coat it with to seal it and keep it as a quick replacement.
    #1
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  2. ShaftEd

    ShaftEd Long timer

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    Thanks windblown101, very nice write up. Mine also crapped out at about 8,000 miles. Dealer blamed ethanol was killing the floats.
    #2
  3. windblown101

    windblown101 Long timer Supporter

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    That wouldn't surprise me. I'm guessing Europe doesn't have ethanol laced gas. Quite a bit of history with them having issues with it in their bikes. On the 1190 the float would swell and jam. On some BMWs the fuel strip would crap out. Ducati had gas tanks swell from the stuff. What strikes me as odd is that after all this time they still don't seem to test their components destined for world wide sale with the stuff. Non-ethanol laced fuel is almost as rare as leaded gas in these parts.
    #3
  4. brianbrannon

    brianbrannon They'll ride up with wear

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    Lots of way stronger chemicals in gasoline than ethanol
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  5. windblown101

    windblown101 Long timer Supporter

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    True, however it's in pretty minute amounts as I recall. But sure, I reckon it could be something else in the gas causing it.
    #5
  6. wierpig

    wierpig Adventurer

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    merseyside uk
    Europe has e10 petrol, ie 10% ethanol.In the UK its e5....for now
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  7. Dan D.

    Dan D. Long timer

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    Probably from methanol abuse.

    Fun read. You're a curious fellow.
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  8. windblown101

    windblown101 Long timer Supporter

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    The world is a curious place. I should fit right in! :)
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  9. BHoward

    BHoward Been here awhile Supporter

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    Dang Windblown, you sure are a busy guy. 25,000 miles on the 790 and a excellent write up. Thank you.
    #9
  10. windblown101

    windblown101 Long timer Supporter

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    Thanks. Trying to see how much abuse it will take before it cries uncle in a big way.

    I had to cry uncle for a minute but I'm just about ready for round three.
    #10
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