Wing Tank revelation, embarassment, mystery, and more

[astjp2]

Re: Wing Tank revelation, embarassment, mystery, and more

Old tanks were tern plate, newer ones were aluminum. The original Manufacturer of the caps was Lebow Eaton, you can have them built but you need to be prepared to drop a couple grand, they will tool up from what I hear for a large quantity. Or just Call Doug Combs and see if he has any that will work. When it comes to Gaskets, get the ones that are Mogas (auto) safe, some of the aircraft ones turn to goo when wet with auto gas. A good fab shop can punch out the tabs pretty easy, brazing is simple, just time consuming. When you need a header tank valve, let me know. I seem to know more about fuel systems than I really want to.

One design improvement is to put the vent above the boundary layer when at a high angle of attack, keeps positive pressure all the time on wing tanks in all of the flight envelope. The atlee caps have that feature. Cub drivers were going negative pressure in their tanks causing fuel starvation. Original is not always better....
Tim

[flyguy]

Re: Wing Tank revelation, embarassment, mystery, and more

I'm OK on caps here, but my question is: Are the tabs some kind of requirement. How about caps without the tabs?
DC

[M Towsley]

Re: Wing Tank revelation, embarassment, mystery, and more

Tabs make it easier to remove and also have the capacity stamped on them. Not required, plenty of caps out there on airplanes without tabs. The tabs just make them 'correct'.

[flyguy]

Re: Wing Tank revelation, embarassment, mystery, and more

Thanks Marty. Pretty much what I figured.
Darryl

[hisoos]

Re: Wing Tank revelation, embarassment, mystery, and more

Ok, gents, I got out to play with wing tank yesterday. At first I thought not metal when I got to drilling because it was a dark material, then I DID hit metal. Anyway it is drilled and I did some flushing yesterday. (Left tank only). I still need to drill the stuck plug on the right tank and work on it. Also worked on cleaning up the caps some more and installed new seals.

Still much work, testing fuel flow, and leak checks to do, but I have a bigger unrelated issue. New thread coming for that.

[Guest]

Re: Wing Tank revelation, embarassment, mystery, and more

Ok, gents, I got out to play with wing tank yesterday. At first I thought not metal when I got to drilling because it was a dark material, then I DID hit metal. Anyway it is drilled and I did some flushing yesterday. (Left tank only). I still need to drill the stuck plug on the right tank and work on it. Also worked on cleaning up the caps some more and installed new seals.

Still much work, testing fuel flow, and leak checks to do, but I have a bigger unrelated issue. New thread coming for that.

try heat if you can, may avoid drilling

[hisoos]

Re: Wing Tank revelation, embarassment, mystery, and more

Thanks drude, but we are beyond heat. Nothing to grip to anymore, the square head broke off. Curious your approach to apply heat without catching fabric on fire? I experimented a little with a shield while trying some heat, but go nervous.

[Guest]

Re: Wing Tank revelation, embarassment, mystery, and more

Thanks drude, but we are beyond heat. Nothing to grip to anymore, the square head broke off. Curious your approach to apply heat without catching fabric on fire? I experimented a little with a shield while trying some heat, but go nervous.

I have done as you did, metal shield plate with hole for access to the part in question and lots of wet drippy towels against the fabric and behind the plate. I did that for welding. For the tank fitting would do the same pus fill the tank with water.

I have found success in removing the 1/8" MPT "plugs" by heating the center of it with the cone of an acetylene torch for about a count of 4. Then they unscrew easily, works most of the time but sometimes not.

Dave R

[N96337]

Re: Wing Tank revelation, embarassment, mystery, and more

If you can give it a 200* temp rise, you'll usually get it out. That can be accomplished with a heat gun (if you have one of those awful things in your arsenal) or I usually try to use a butane/propane torch. Like Dave says....just for a short count. Sounds like an easy out is in order for you... if you do it right, you wont have to drill all the way through, and save yourself getting any chips inside the tank with the drill.
John

[hisoos]

Re: Wing Tank revelation, embarassment, mystery, and more

If you can give it a 200* temp rise, you'll usually get it out. That can be accomplished with a heat gun (if you have one of those awful things in your arsenal) or I usually try to use a butane/propane torch. Like Dave says....just for a short count. Sounds like an easy out is in order for you... if you do it right, you wont have to drill all the way through, and save yourself getting any chips inside the tank with the drill.
John

Agreed easy out is my next step. But first things first (reference other thread)