Leaky Header Tank

[djmc4344]

I may need to change my header tank in my model iv because of a problem leak at the bottom fitting bushing. I think the threads were tapped to deep or I may have tightend to much. My question; is the rotational moulded tank from Kitfox the way to go or are there other options? Does the Kitfox tank have the brass fitting molded in?

Thanks for your opinions in advance, this problem is holding up my first flight.

[DesertFox4]

Dan, Check with John or Deb at Kitfox Aircraft about their aluminum header tank. You get a little more capacity and it is very durable. It also has the built in low fuel sensor. You'll love it and no more leaks in the cabin. I bet they have them in stock and ready to ship.

[wadeg]

Recently replaced my leaky molded header with the new aluminum one. Perfectly sealed now. I'd go with the aluminum from the 'get-go'.

[Av8r3400]

Too bad we can't get Aluminum wing tanks, too...

[djmc4344]

Problem fixed, installed a new Plated steel bushing (sharp threads) applied Permatex 9 AR Tack and Seal. Let it set a few days , no leaks to date. Thanks for all the responses.

[Paul Z]

My wife and I just got back from Mesquite Airport, working on 703KA. I have been smelling fuel in the cabin, we removed the seat, to check the fuel lines, and found that the header tank is leaking from the two outlets from the pilot side of the tank. The fumes were very strong. When we took the seat up we could see a stain spot on the bottom coving of the plane. It is obiously not a bad leak. However you can see a stain going down the side of the header tank (Pilots Side) and on the skin below the header tank on the Pilots side of the plane. II'll be talking with John Monday!

[Paul Z]

I was planning on taking the wife flying today, but I didn't want to risk it with this issue. Considering one of my flight instructors, Jim Phillips got to watch his Steerman Bi-Plane torch because of a fuel leak. I figured it was not prudent to fly, considering we smelled gas. We loosened the front screws for the seat, picked it up slightly, and at first I couldn't feel any fuel or see a leak. We decided to completely remove the seat, and propped up the seat bottom, I could see a very slight stain down the side of the header tank, and on the floor of the plane. I plan on talking with John to see if I can remove the fittings, and reinstall them to seal the leak. Every new vehicle has some squawks, after being built, so it's no big deal. I just don't want it to get worse, and I don't want to risk catching the plane on fire.

SO MY POINT TO ALL IS BE CAREFUL! DO A THROUGH PREFLIGHT, AND FLY SAFE! THAT WAY WE CAN KEEP THE KITFOX :D !!

I believe John sells an Aluminum header, I may see about putting in one of those.

[DanB]

Paul,
I'm glad to see this type of decision not to fly while smelling fuel. We have kicked this topic around while doing some hanger flying recently and the conclusion is if you can smell gas at all, the leak is too big and the plane should be grounded. The argument that our little planes are drafty does not hold water for me...as fumes, draft and a spark do not make good cockpit companions. We all take calculated risks and I hope with this one everyone uses a calculator

[Paul Z]

Well I finally found the sealant recommended for the header tank Permatex AR9(???). I don't remember the sealant. It is the sealant John McBean recommends. I removed the drain plug, and the return line, cleaned, put on new sticky stuff, and reinstalled it worked GREAT! I put a light coat on both the male and female threads screwed it all together, snugging the pipe thread into the header tank after I screwed the fittings into the pipe thread adapter. Man now that is some Sticky Sealant, you don't have to worry about the fittings backing out!! I got some between my fingers and I thought I was going to have to have them surgically seperated to get them apart. At least now I don't have to worry about catching the plane on fire for that leak. Thanks John for the phone help and advice, I'll send some pictures.

[Paul Z]

Well I went to the airport today, still no leak. I put the seat bucket back in, seat pades, and then pulled it out for a test flight. Once around the patch, someone coming in on a ILS approach, so I get to go around an do some flying. I headed North, some rain and lightening, so I head back to the airport. I had a good short flight with no gas fumes to distract me.

[DesertFox4]

Good to hear Paul. So you're our "go to guy" for leaky plastic header tank sealant in the future.;) Maybe you can post the exact number and mfg. of the sealant for the archives.

[Paul Z]

It's Permatex 9AR, Item Number is 80938. I went to 5 different Auto Parts before I found it. They Stock it under the item number, not 9AR!


Permatex® Tack & Seal™ Gasket Sealant

Non-hardening for easy disassembly. Keeps
large gaskets in place during positioning and
assembly. “Clean hands” formula won’t stain.
Temperature range -65°F to 400°F (-54°C
to 204°C); resists engine fluids including
diesel fuels and synthetic oils.


Suggested Applications: Seals air conditioning,
fuel fittings, radiator hoses, PVC
fittings and cork, paper, cardboard, felt
and metal gaskets

Item # Container Size Pack Old P/N

80938 1.25 oz. tube, 12 9AR

[jdmcbean]

We also keep it in stock if you cannot find it.