how to clean BMW gas tank?

Discussion in 'Old's Cool' started by wintonio, Jan 27, 2007.

  1. wintonio

    wintonio last of the Dum Dum Daze

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    Apr 21, 2006
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    1,657
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    Castle Rock, CO
    OK, to say I don't know my ass from a hole in the ground might be an understatement.
    I have a '92 R100GS. What do I use to clean out the tank? It is the metal kind, with the paint on the inside. The dealer told me to use fresh gas, let it dry, use more fresh gas, I presume swirling it around, then let it dry again. At this point, I am almost afraid to try anything my local dealer says. SO. what should I use, and what is the technique?

    Note: I am not currently having any problems that I am aware of, just doing some maintenance.
    #1
  2. JohnTM

    JohnTM I suck toes

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    Oct 20, 2001
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    29,206
    Location:
    Cornersville, TN
    What condition is the inside paint in, and what is in the tank, rust? Or is is just stale gas?

    If the lining is good and there is just gas crud, then your dealer has it right. If the lining is bad and there is rust, then it's a whole different story.
    #2
  3. budsboy

    budsboy Well-Seasoned

    Joined:
    May 31, 2004
    Oddometer:
    124
    Location:
    Northern Michigan
    The way to clean the tank is -
    Fill with fresh gas
    Ride bike untill all the gas is gone
    - Repeat

    No need to do anything else -
    #3
  4. wintonio

    wintonio last of the Dum Dum Daze

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    ok, I can do that. Like I said, there is no rust that I am aware of. I have just read that it is good to clean the tank out once a year, to make sure there is no water in there etc., so I was looking for the procedure for that.
    #4
  5. RocketJ

    RocketJ Been here awhile

    Joined:
    Nov 29, 2005
    Oddometer:
    674
    Water is the universal solvent. I use hot tap water with dish soap. Slosh it real well. Repeat. Rinse with hot tap water till it all comes out clear. let it dry in the sun for the afternoon. Next day, slosh some clean gas all around to get rid of any left over water.
    You will be suprised how much crap comes out this way that plain gas leaves behind. YMMV
    #5
  6. RandyB

    RandyB .

    Joined:
    Jan 11, 2006
    Oddometer:
    5,072
    I just took my GS tank to the car wash after pulling the petcocks. .75 later and it was clean. One full tank of soap and the rest rinse. The liner was peeling and clogging the screens.
    #6
  7. jdiaz

    jdiaz .

    Joined:
    Feb 27, 2002
    Oddometer:
    32,348
    Location:
    Flyover State
    Yep, this is what I do as well. The 1/2-inch of gas left below the reserve tap holds a ton of junk in the tank that riding around will not get rid of.
    #7