Accessory Replacement - Piper Navajo PA-31 Service Manual

PIPER NAVAJO SERVICE MANUAL
9-13b REPAIR PATCH (AIR CURE METHOD)
NOTE
A minimum of 72 hours curing time at 70°F is required per
patch. A minimum of 144 hours is required to install an outside
and inside patch. Add 20 hours cure time for each 10°F drop in
temperature. Never attempt to air cure at temperatures below
60°F.
a. Follow the procedure for the heat cure method, except omit the following:
1. Omit cure iron from steps 18 and21.
2. Omit steps 19 and 21.
b. Refer to fuel cell repair limitations for curing time.
9-13c. METAL FITTING - SEALING SURFACES.
a. Rub off roughness of affected area with a fine file or fine emery cloth. Treat reworked area.
b. Clean metal surface using a clean cloth dipped in Methyl Ethyl Ketone. Moisten cleaned surface with
clean cloth dipped in water. Apply alodine 1200 solution, undiluted, to the affected area with a small nylon
brush. Allow solution to dry until a light golden color appears. When coating has been formed, remove excess
solution by wiping with a clean water-moistened cloth. Allow coating to dry.
WARNING
Do not allow solution to come in contact with hands, eyes or
clothing.
9-1 3d. ACCESSORY REPLACEMENT.
a. Obtain cured repair accessory from cell manufacturer.
b. Mark location of old accessory and preserve markings for guide lines to locate new part.
c. Remove old accessory by gradually loosening an edge with a blunt probe-like instrument.
d. When a loose edge is created, grasp accessory by loose edge with pliers and gently pull accessory off
cell wall. Be careful not to pull cell lap open while peeling accessory off. Pull from blind side of a cell lap
toward the exposed edge.
e. Buff the cell surface under accessory with emery cloth to smooth roughness and prepare for cement.
NOTE
Removal of old accessory will probably leave an uneven cavity
and surface.
f. Prepare replacement accessory by buffing and washing contact surface. Also wash cell surface (see
repair patch).
g. Apply mixed 80C27 repair cement to both surfaces being sure to level cavity left by removal of old
accessory.
h. Roll new accessory into place as with a repair patch and place suitable padded plates in position to
insure adequate pressure when clamped. Use cellophane separator to prevent cement sticking in the wrong
place.
i. Cure as with repair patch either cure method.
Revised: 2/18/94
FUEL SYSTEM
3B9