Register now to get rid of these ads!

Technical Tanx fuel tank question

Discussion in 'The Hokey Ass Message Board' started by Tids32, May 6, 2018.

  1. Tids32
    Joined: Jun 2, 2009
    Posts: 12

    Tids32
    Member

    I have a Tanx fuel tank that I'm planning on running in my 31 Studebaker. It's designed for a 33 Plymouth, but it's close enough to fit well. I won't be using the pickup tube, as I've fabbed an adapter to use the original tube at the top of the tank, so I want to block it off. A 1/4npt plug fits, but goes in too far to be npt threads, so must be straight. What's the best way to seal this hole? I'm not familiar with this style fuel hookup. 20180506_160408.jpg

    Sent from my SM-G955U using The H.A.M.B. mobile app
     
    chryslerfan55 likes this.
  2. MrMike
    Joined: May 21, 2010
    Posts: 138

    MrMike
    ALLIANCE MEMBER

    Why not contact Tanks and ask them what they recommend?.
     
    timwhit likes this.
  3. RMONTY
    Joined: Jan 7, 2016
    Posts: 2,188

    RMONTY
    Member

    Thats not an inverted flare fitting on the inside is it?
     
  4. Tids32
    Joined: Jun 2, 2009
    Posts: 12

    Tids32
    Member

    Will be doing that tomorrow. I figure this is a modern standard used in newer cars, and someone may have been though this before.

    Sent from my SM-G955U using The H.A.M.B. mobile app
     

  5. gimpyshotrods
    Joined: May 20, 2009
    Posts: 18,122

    gimpyshotrods
    ALLIANCE MEMBER

    That appears to be a fitting designed to take a 5/16" inverted flare fitting, which I believe was the stock Plymouth line size.

    Inverted flare line, showing tube, and tube nut:
    [​IMG]

    The threads on a 5/16" tube nut are 1/2"-20. You should be able to get an inverted flare plug at a decent auto parts store.

    Inverted flare plug:
    [​IMG]

    Same sealing surface, same basic shape, but the plug has no hole for a tube in it.

    It is noting new. Inverted flare fittings were the de-facto standard by the 1930's, and are still used, in one form, or another, today.
     
    Hnstray likes this.
  6. Tids32
    Joined: Jun 2, 2009
    Posts: 12

    Tids32
    Member

    Took a better look at this, and the bottom of the fitting is flat. If it was for a flared fitting, I would expect to see a beveled bottom that would seal against the flare. Maybe just an o-ring gasket and a short bolt would do. I'll call the manufacturer tomorrow and find out for sure what they recommend.

    Sent from my SM-G955U using The H.A.M.B. mobile app
     
  7. gimpyshotrods
    Joined: May 20, 2009
    Posts: 18,122

    gimpyshotrods
    ALLIANCE MEMBER

    If it is an inverted flare fitting, flare plugs are very easy to get. I strongly caution against using a substitute, as a failure here means a fuel leak.

    Fuel leaks can leave you stranded, at minimum. At maximum, you can lose more than just your car.
     
  8. Tids32
    Joined: Jun 2, 2009
    Posts: 12

    Tids32
    Member

    Ok. - it's supposed to be an NPT fitting, but either the weld flange or my plug was cut wrong, allowing it to bottom out, instead of seal. I really hope it's the plug that's wrong.

    Sent from my SM-G955U using The H.A.M.B. mobile app
     
  9. alchemy
    Joined: Sep 27, 2002
    Posts: 16,853

    alchemy
    ALLIANCE MEMBER

    Shorten up the narrow end of your plug.
     
    gimpyshotrods and Hnstray like this.

Share This Page

Register now to get rid of these ads!

Archive

Copyright © 1995-2021 The Jalopy Journal: Steal our stuff, we'll kick your teeth in. Terms of Service. Privacy Policy.

Atomic Industry
Forum software by XenForo™ ©2010-2014 XenForo Ltd.