Fuel Tank Bay Repairs

[Kyle]

Sorry - this needs to be in the "Hanger" and I can't figure out how to move a draft from one forum to another...
Mod: You can't move it but I can

During the last annual we addressed the continuing contamination of our right fuel tank. I decided to pull the tank, clean it, prep the tank bay and re-install everything. Hoping of course it would not need another visit for another 60 or so years. It was worth the effort. Fore and aft in the bay are small wooden blocks ("spacer" IPC Fig. 8, index # -8, p/n 0523524) that help keep the tank properly placed in the bay. The rear block was installed with truss head screws. Once the rear block was out, and all the tank plumbing was disconnected the tank came out of the bay easily. The tank straps had dried / cracked chaffe padding and we replaced it with new. Using clothes pins worked great to hold new chaffe strips on untill the glue dried.

The rear inboard spar had a small amount of corrosion that was removed. The tank bay was preped, etched and alodined including all surfaces that would come in contact with the tank cover. The bay was primed once ready. The two small dings on the tank were heli-arc welded (once the tank was flushed and gas free). Any corrosion on the tank was also removed and treated. The tank cover was treated and painted paying special attention to areas that would come in direct contact with metal.

In order to access some of the tank plumbing inside the cabin, the headliner needed to be pulled back. Since we were up in that area, and I had been following Greg's teriffic job of soundproofing his 170 over in Plymouth, - well that's another post. Here are a few pictures...

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[hilltop170]

Nice looking job, are you going to re-install the wooden blocks? If not what will replace them?

[Kyle]

We cleaned the wooden blocks, replaced the cork pad on each with rubber and re-installed.

[lowNslow]

Kyle, how did you the treat the inside of the fuel tank for contamination?

[Kyle]

Karl,

Sorry should have been more descriptive, only the exterior of the tank was treated, etched, alodined and primed...

[DaveF]

Thanks for the write-up. This is on my to-do list.

[FredMa]

While doing this repair, it would be a good time to coat the paint with some type of corrosion inhibitor like Cor-Ban 35 or equivilant.

[GAHorn]

Paint ...IS..an anti corrosion treatment.
Painting ...paint...with another product ...unless it is a sealer... is not likely beneficial and, depending on the type of paint, may cause deterioration of the paint (and loss of it's protective capability.)

And some anti-corrosion products are nasty about attracting dirt and grime. Not a good thing where chafeing might occur or where inaccessibility can prevent regular cleaning.