BMW G650GS fuel pump housing leaking

Discussion in 'Thumpers' started by BingoPlusTwo, Sep 8, 2021.

  1. BingoPlusTwo

    BingoPlusTwo Adventurer

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    I woke up this morning to a puddle of fuel in my garage under my bike. It turns out that when the bike is running, fuel leaks from under the fuel pump "cap," the part that screws onto the fuel tank, holding the fuel pump. Anybody else seen this? I believe the previous owner replaced the fuel pump, so possibly improper installation? Is there a sealant there that I need to apply or reapply? I suppose I need to pull it out and have a look; that's happening soon. I'd love to have advice from those that have trod this path before me. Many thanks.
    #1
  2. Gedrog

    Gedrog 1000 mile stare a 1000 stories to tell

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    Welcome main forum lots of good lads & ladets
    https://advrider.com/f/threads/2012-bmw-g650gs-sertao-owners.747861/

    There is a rubber seal between the Pump and the tank below is from the twin-cylinder F650GS but the part looks the same in the picture it is away from the top wrapped around the pump
    Easy to get the rubber seal wrong it is a bit fiddly


    h[​IMG]
    #2
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  3. BingoPlusTwo

    BingoPlusTwo Adventurer

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    Perfect. Thanks. I'll fiddle with it tomorrow morning I suppose.
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  4. CarstenB

    CarstenB Been here awhile

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  5. BingoPlusTwo

    BingoPlusTwo Adventurer

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  6. roookie1

    roookie1 Been here awhile

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    Maybe just needs a bit more tightening..
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  7. BingoPlusTwo

    BingoPlusTwo Adventurer

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    Good call, and I tried that a bit. The hard part is that, like most, I don't have the special wrench, so I'm left with a block of wood and a hammer. The last thing I want to do is break something larger here. Regardless, I was able to coax it to tighten a few more degrees and it is still leaking. So I ordered the rubber gasket as recommended above and when it gets here I'm going to take it apart. I wonder why it just started leaking yesterday, though. I've ridden it about 120 miles since I bought it (used, obviously). I filled it with gas for the second time just prior to it leaking, so did the gasket just fail yesterday? I hope it isn't a broken pump housing, but I was happy to find that the housing is common to a bunch of BMW cars, so perhaps it will be easy to find if the housing is, in fact, cracked.
    #7
  8. WayneC

    WayneC Long timer

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    There were some G Series delivered with an incorrect seal which leaked well after sale, the seals were replaced by BMW under an NHTSA TSB
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  9. BingoPlusTwo

    BingoPlusTwo Adventurer

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    Update: opened the fuel tank and was happy to see a torn seal. I suspect the previous owner showed it to me low on gas because every time he filled it and put it on the stand it leaked. $8 seal, I’m thrilled. The part arrives by UPS tomorrow.

    I didn’t see any cracks or issues with the pump housing, which made my day. Even better if I can put it back together with no leaks.

    Attached Files:

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  10. BingoPlusTwo

    BingoPlusTwo Adventurer

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    Any advice on how to install the new seal correctly?
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  11. sledrydr

    sledrydr Been here awhile

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    I had a F650GS that leaked at startup. Once? Never did it again which was odd/fortunate?
    Anyway. On gasoline related seals I have used 2 stroke oil on the seal to help/encourage it to fit easily. Not sure if this will help but it may be worth considering if it fights you! Good luck.
    #11
  12. BingoPlusTwo

    BingoPlusTwo Adventurer

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    That’s a great idea. I was thinking about lubricants and that’s the perfect one. Thanks.
    #12
  13. BingoPlusTwo

    BingoPlusTwo Adventurer

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    SUCCESS! Replaced the seal last night after the world’s latest UPS delivery. Drove it to work today.

    @sledrydr your 2-cycle trick was money. I don’t think I’d ever have gotten that seal seated dry and I almost tore it exactly like the last guy did. 100% I’d have torn it if I hadn’t used some lube.

    Thanks to all!
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  14. motobene

    motobene Motoing for 51 years Supporter

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    Silicone grease (plumber's grease) for installing rubber like that helps prevent damage/tears and wonky installs.
    #14
  15. BingoPlusTwo

    BingoPlusTwo Adventurer

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    Do you think that would be safe to use in the fuel tank?
    #15