Tubeseal Internal Tubing Corrosion Inhibitor


Tubeseal is a blend containing a very fine preservative oil (REF: MIL. SPEC. L-21260), which has a characteristic of climbing the tube wall and spreading over the entire surface to provide lasting protection. Prevents rust and corrosion inside aircraft tubing structures.

Tubeseal will penetrate and reveal very small pin holes in a weld and, in time, due to exposure, congeal and seal the hole.

One quart is sufficient to treat a 1- to 4-place aircraft fuselage and miscellaneous tubular components.


1. Drill a No. 30 (.128) hole on top side of tube approximately 1.5" from an end. Holes are usually drilled before welding is completed for venting purposes.

2. Insert into each tube section the following quantity of inhibitor:

5/8" dia. or less - 1.0 cc per ft

1.0" dia. or less - 1.5 cc per ft

1.5" dia. or less - 2.0 cc per ft

2.0" dia. or less - 3.0 cc per ft

3. Close all holes with pop rivets No. AD-41H (closed end type).

4. In order to insure complete internal wall coverage, rotate fuselage or other welded tube assembly to assure all tubes are cycled from upright thru 90° to side, then 90° to inverted, then 90° to opposite side and finally 90° back to upright. A minimum of 5 minutes waiting period should punctuate each 90° arc. Room temperature during application should not be lower than 60°F.

Process approved by FAA during certification of Stits Skycoupe Model 9A. TC No. 4A-31.


Infinite, in sealed containers in protected storage Not affected by freezing.


One-pint and one-quart cans.