Fuel Tank Fittings

[builderflyer]

hi all,
we had a very small leak in one of our legacy molded in tank fittings. we used a glue from locktite, called a plastics bonding system. has a primer stick, and tube of glue. looks exactly like a super glue tube. red/blue package. no part number, but bar code on back is 7934082565. for all plastics , poly e and poly p. our fitting on the lower rt sump in tank on verticle side started to barely drip. we drained tank, let sit for a few days. took out brass plug. cleaned outside with scotch brite, wiped w acetone, primer stick tank and fiber washer. glue applied on tank, fiber washer metal washer screw. tightened up. never leaked since. locktite sells this. mfgr is henkel corp, rocky hill ct. this fitting was never used, go figure. avbl from home depot, lowes, ace hardware, true value.

WaiexN143NM
Michael

After flying my Sonex for 15 years I tempted fate one too many times when I installed a red cube fuel sender unit just downstream of the tank shutoff valve. Oh no, the main fuel tank outlet fitting began to leak around its perimeter after being disturbed by this work. So I tried something like what Michael describes above in his message. I made a 1 1/2" o.d. washer out of a potato salad container lid. It is made from polypropylene (#5 plastic) and was glued to the tank using the Loctite product mentioned in Michael's message. Although probably not necessary, I used J-B Weld around the pipe where it went through the pp washer (with its paper label intact)to help stabilize the pipe connection to the washer and the tank.

It's now been about 6 months and about 50 hours flying time and so far no return of the leak. So thank you Michael for pointing out that it might not always be necessary to go to the trouble of installing an oops fitting for a relatively small leak.

Thinking there would be a need for more than one package of the Loctite product, I bought three online and used less than one. So if anyone has a need for this stuff, I'd be happy to mail it to to you before the shelf life runs out, if there is one.

Art,,,,,,,,,,,,,,,,,,Sonex taildragger #95,,,,,,,,,,,,,,,,,Jabiru 3300 #261

[WaiexN143NM]

hi art, all,

glad to hear this worked for you. yes this glue for poly e and p plastics. not much else may bond to the tank so use caution. oops fitting, easy to install on a tank on your work bench. on an installed tank, well you will learn some new four letter words. just hard to get at. under the panel and if your over 60 , arthritis, etc is hard to do.
good job art! glad it worked for you.
it will prob last a long time. packaged and looks just like super glue gel.

stay safe,

WaiexN143NM
Michael.

[n502pd]

I too had a small drip from the lower. right hand, not used fitting, almost from day one, that was worse in the winter, and gone in the summer. I finally tried to gently tighten it, but made it worse. Yep, drained, cleaned, replaced the torn O-ring (probable cause) and liberly applied 'Turn lubricant', known as fuel lube, every where I could get it. reinstalled the outer nut on the oops fitting, and not a drop for 3 months. fuel lube is impervious to any petrolium product...wont disolve...and is my item of choice for things that leak fluids, like rockerbox covers, pushrod tubes, gaskets, crush washers, bolt threads, and etc. the big thing is that hardware can be easily removed anytime. a tube will last a very long time. From ACS.