How to seal threads on emblem screws

Discussion in 'Airheads' started by rbm, Feb 18, 2013.

  1. rbm

    rbm Adventurer

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    Hi,

    I'm going to be modifying my BMW K75 tank to accept /5 tank emblems using screws rather than adhesive. This means drilling and tapping the aluminum. Will I need to use a sealant (such as Locktite 242 or RTV) to seal the threads when installing the badges, so that there is no possibility of fuel leakage later? Or is the rubber gasket between the badge and tank sufficient to stop leakage?

    I had also contemplated using slightly longer screws with flanged nuts on the inside of the tank. Bad idea?

    BTW, posting in this forum since it's more likely to have someone in the know read this than in another forum, like Road Warriors.
    #1
  2. crazydrummerdude

    crazydrummerdude Wacky Bongo Boy

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    I have a hard time believing that this idea won't leak regardless of the sealant.
    #2
  3. Boxer Metal

    Boxer Metal Mad Scientist

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    Weld in an aluminum nutsert. You could also cut the heads off of the screws, JB Weld them in place and use 3M double sided tape to hold the emblems on.
    #3
  4. bikerfish

    bikerfish flyfishandride

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    I second the "fake screw" idea. just glue the heads onto the emblems and use the tape to hold the emblem on, nobody gonna know!
    #4
  5. Airhead Wrangler

    Airhead Wrangler Long timer

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    I wouldn't penetrate the wall of the tank if I were you. That seems like a losing proposition no matter how you seal it up again. I'd have someone weld or braze a blind threaded insert into the wall of the tank and screw them into that.

    EDIT: Considering the difficulty involved in doing the above, the 'fake screw' and adhesive method mentioned earlier is what I would do.
    #5
  6. Bill Harris

    Bill Harris Confirmed Curmudgeon

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    That is how the /5 (and earlier) tanks do it.

    That is how I would do it.

    --Bill
    #6
  7. kantuckid

    kantuckid Long timer

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    plus 1,000,000+!!!!!
    #7
  8. Kai Ju

    Kai Ju Long timer

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    Most folks here try and seal old tanks that have holes in them, here you want to go and make holes.............

    Fake the screws, nobody will know, whereas if you drill the tank and it leaks it will show :D
    #8
  9. rbm

    rbm Adventurer

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    Well, good I asked. I got consensus on faking the screws and using double-sided tape so that's the way I'll tackle this modification. Thanks to everyone who responded.
    #9
  10. bmwhacker

    bmwhacker Still on 3 wheels

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    Go ahead admit it...you want a /5:lol3
    #10
  11. wmax351

    wmax351 Been here awhile

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    If I recall, the K bikes have a double wall tanks. In any case, cut off the heads, and glue it on.
    #11
  12. Boxer Metal

    Boxer Metal Mad Scientist

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    Nope on the double walls.
    #12
  13. wmax351

    wmax351 Been here awhile

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    Good to know. I have a little dent from someone's handlebar I need to pop out.
    #13
  14. rbm

    rbm Adventurer

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    Ya. Wouldn't mine in the least!!:ricky
    #14