Bearhawk Aircraft Bearhawk Tailwheels LLC Eric Newton's Builder Manuals Bearhawk Plans Bearhawk Store

Announcement

Collapse
No announcement yet.

AN fuel tank fittings

Collapse
X
 
  • Filter
  • Time
  • Show
Clear All
new posts

  • AN fuel tank fittings

    I am putting the AN fittings in my right tank tomorrow and did some test fitting today. I did it dry, but will use EZ Turn for the actual installation.

    My question is do the tank receptacles need to be tapped as it seems they are very tight and I don’t want to over torque things. The finger strainer (brass) is also very tight for the AN to go inside prior installation in the tank.

    Thoughts?
    N678C
    https://eaabuilderslog.org/?blprojec...=7pfctcIVW&add
    Revo Sunglasses Ambassador
    https://www.youtube.com/channel/UCQ0...tBJLdV8HB_jSIA

  • #2
    You should not have to tap the tank fittings. EZ turn lube will make it much easier to tighten the AN fittings. I didn’t use a torque wrench on the AN fittings for the tank, just snugged them up pretty good, wiped away any excess EZ turn and went on, haven’t had any issues with leaks.

    Comment


    • #3
      Pipe threads are tapered. The farther in you thread them, the harder it gets, and that's how you want it. Be careful not to overtighten, since that is like driving a wedge into the hole.

      Comment


      • #4
        It gets tricky when you have to clock a 45 degree fitting. Evidence showed that my bungs stretched some (or the fitting compressed). Just Treat the threads with sealant, install and clock it. Do it once and move on. Don't think your ahead of you trial fit it. I'd be interested if my experience was duplicated by others.
        Brooks Cone
        Southeast Michigan
        Patrol #303, Kit build

        Comment


        • #5
          The fuel outlets are 3/8 NPT threads. I have used a tap on a couple that did not allow the fitting to go in enough for my taste. Cheap tap that costs $5-$7. You want a few threads engaged so tap if you need to get that.

          But all the suggestions above are good. Use the EZ turn first to see if that helps you get another thread or two engaged. Mark

          Comment


          • #6
            Mine were also very tight, if you're are anything like mine - certainly don't try and run the fittings all the way home.

            I was hesitant to tap the NPT threads, as it would be easy to oversize them and then you have a bigger issue. Provided you use plenty of appropriate sealant (i.e. liquid sealant only), then you will not have any issues with leaks. Provided you don't rotate the fittings once they are sealed up.

            If you assumed they would sit flush, like me, then found out the brass strainer and AN fitting actually stick out a lot (maybe a couple of inches or something like that) then your layout might need to change to accommodate the length of the fittings.

            Comment


            • #7
              Thanks for all the feedback

              I used the EZ Lubricant and they went in much easier

              As always you guys have the answers
              N678C
              https://eaabuilderslog.org/?blprojec...=7pfctcIVW&add
              Revo Sunglasses Ambassador
              https://www.youtube.com/channel/UCQ0...tBJLdV8HB_jSIA

              Comment


              • #8
                I don't remember having an issue with the tank bungs. There is a minimum number of engaged threads for pipe threads. I don't remember having a problem with the tank fittings. I do remember have a problem with the strainers. The strainer threads were so tight I was only getting 1.5 engaged threads on the AN fittings screwed into the bronze strainers. I tried a couple of different strainer brands. I ended up running a tap into the strainer.

                Comment


                • #9
                  I built my own tanks with bungs from Spruce. I could not install the fittings in most of them more than a couple threads, no amount of fuel lube was going to fix that. I used a tap on the majority of them to get good thread engagement.

                  Comment


                  • #10
                    Originally posted by svyolo View Post
                    I don't remember having an issue with the tank bungs.
                    They are a welded part, so the amount they change shape could vary - this would be particularly noticeable in the NPT thread.

                    I would not be surprised if some tank fittings are better or worse than others.

                    Comment

                    Working...
                    X