Repair Of Boots; Cold Repair; Scuff Damage; Tube Area Damage - Piper Navajo Chieftain PA-31-350 Service Manual

NAVAJO CHIEFIAIN SERVICE MANUAL
NOTE
Disconnect line fittings from boot fittings.
a.
Starting at one corner of the upper trailing edge of the deicer, apply a minimum amount of
solvent to the seam line while tension is applied to peel back the corner of the deicer.
b. Using a pressure handle squirt can filled with solvent, separate the deicer boot from the surface
for a distance of 4 inches all the way along the upper trailing edge.
c. The area between the deicer and the wing which has now been separated will act as a reservoir for
the solvent, therefore, the deicer can be pulled down towards the leading edge with a uniform tension.
d. From the centerline of the leading edge to the lower trailing edge of the deicer, use the pressure
handle squirt can to soften the bond between the deicer and the wing skin.
e.
Use Kelite 21 or Turco 388 to clean the dry cement off the exposed wing area, and clean the area
thoroughly with MEK (Methyl Ethyl Ketone).
14-76. REPAIR OF BOOTS. Deicer repairs are classified as cold, when made on the boot installed on the
airplane, and vulcanized. made on the demounted boot in the shop. (Refer to Paragraph 14-78 for vulcanized
rep. irs.)
14-77. COLD REPAIR. The materials and supplies for making cold repairs are listed in Table XIV-VII.
a. SCUFF DAMAGE. This type of damage will be most commonly encountered and, fortunately, it
is not necessary in most cases to make a repair. On those rare occasions when the scuff is severe and has
caused the removal of the entire thickness of surface ply in spots (the brown natural rubber underneath is
exposed), repair the damage using Part No. 74-451-16 and proceed as follows:
1.
Clean the area around the damage with a cloth dampened slightly with solvent. Buff the area
around the damage with 74-451-75 emery buffing stick so that it is moderately but completely roughened.
Wipe the buffed area with a clean cloth slightly dampened with solvent to remove all loose particles.
2. Select a patch of ample size to cover the damaged area. Apply one even thorough coat of
cement, Part No. 74-451-20, to the patch and the corresponding damaged area. Allow cement to set a
couple of minutes until tacky.
3. Apply the patch to the deicer with an edge, or the center, adhering first. Work down the
remainder of the patch carefully to avoid trapping air pockets. Thoroughly roll the patch with
stitcher-roller, Part No. 74-451-73, and allow to set for ten to fifteen minutes.
4. Wipe the patch and surrounding area from the center outward with a cloth slightly
dampened with solvent. Apply one light coat of A-56-B conductive cement, Part No. 74-451-11, to the
patched area.
5. Satisfactory adhesion of patch to deicer will be reached in four hours. Deicer may be
inflated for checking repair in a minimum of 20 minutes.
b. TUBE AREA DAMAGE. Repair cuts, tears or ruptures to the tube area with fabric reinforced
patches, Part No. 74-451-16, 17, -18 or-19 depending on size of damaged area.
1. Select a patch of ample size to cover the damage and to extend to at least 5/8 inch beyond
the ends and edges of the cut or tear. If none of the patches is of proper size, cut one to the size desired
from one of the larger patches. If this is done, bevel the edges by cutting with the shears at an angle.
NOTE
These patches are manufactured so that they will stretch in one
direction only. Be sure to cut and apply the patch selected so that
stretch is in the widthwise direction of the inflatable tubes.
Reissued: 9/23/80
ACCESSORIES AND UTILITIES
4 G4