Fuel Cell Compartment - Piper Navajo PA-31 Service Manual

PIPER NAVAJO SERVICE MANUAL
9-5. FUEL CELL COMPARTMENT.
a. Thoroughly clear the cell compartment of all fittings, trimmings, loose washers, bolts or nuts.
b. Round off all sharp edges of the fuel cell compartment.
c.
Inspect the fuel cell compartment just prior to fuel cell installation.
d. Tape over all sharp edges and all rough rivets.
9-6. MOLDED NIPPLE FITTINGS. The molded nipple fitting is a lightweight fitting developed for ease in
installation in certain locations in the airplane. In order to get the best service from this type fitting, it is
necessary to exercise certain precautions at the time of installation. The specific precautions other than the
general care in handling are as follows:
a. Insert the outlet tube finger strainer into the fitting as shown in Sketch "B." Figures 9-2 and 9-3.
b. Insert the vent tube into the fitting until the end is flush with the inside edge of the nipple.
c. The hose clamp must be clear of the end of the fitting by 1/4 inch where possible.
d.
Locate the hose clamp on the fabric-reinforced area of the nipple.
e. Torque the hose clamp to 4045 inch-pounds. Do this once. Do not re-tighten unless the hose
clamp is loosened completely and allowed to set for 15 minutes before re-tightening.
CAUTION
For aircraft using new BTC-85 Const fuel cells (Piper Part
Numbers, 71028-2, 71028-3 and 71027-2, 71027-3) must use the
following torques on hose clamps.
1. Outlet hoses = 15 to 20 inch-pounds.
2. Drain hoses = 12 to 16 inch-pounds.
3. Vent hoses = 12 to 16 inch-pounds.
f. Do not use sealing paste or gasket compound.
g.
Apply a thin film of Simonize Wax to metal flow tubes to facilitate installation and removal.
Reissued: 10/12/79
FUEL SYSTEM
3A20