To Replace The Bearing Cup - Piper Navajo Chieftain PA-31-350 Service Manual

NAVAJO CHIEFTAIN SERVICE MANUAL
c. Inspect bearing cones for nicks, scratches, water staining, spalling, heat discoloration, roller wear,
cage damage, cracks or distortion. Replace if any of these conditions exist or if cones show signs of wear.
Repack bearing cones with clean bearing grease MIL-G-81322.
d. Wash the inboard bearing seal (9) in isopropyl alcohol and dry with a clean, soft cloth.
e. Visually inspect all parts for cracks, distortion, defects and excessive wear.
f. Inspect inboard bearing seal (9) for wear or damage to sealing lip or to metal reinforcing ring.
Replace if damaged or deformed.
g. Inspect wheel sub-assemblies (5 and 6) for cracks, corrosion or other damage. Cracked or badly
corroded castings should be replaced. Small nicks, scratches, or pits in the castings should be blended out
with fine (320-360 grit) wet-or-dry aluminum oxide cloth.
h. Check bearing cups (7) for tightness, scratches, pitting, corrosion, or evidence of overheating. If
any of the defects exists, replace the cup in accordance with Paragraph 7-72, a.
i. Inspect valve stem hole of outboard wheel assembly (5) for cracks or corrosion. Replace cracked
assembly. Pits, nicks, or corrosion may be polished out with fine (320-360 grit) aluminum oxide cloth,
wet-or-dry.
j.
Inspect wheel bolts (10). Carefully check for cracks in radius under bolt head and in first two
threads adjacent to the bolt shank. Replace cracked bolts.
NOTE
No refinishing of bolts is permissible.
k. Check self-locking nuts (16) for self-locking feature. Replace if nut can be turned onto bolt with
finger pressure.
1.
Inspect keyway liners (12) on inboard wheel sub-assembly (6) for wear. If distance between
surfaces of liners across any tang slot of inboard wheel sub-assembly exceeds 0.620 of an inch, drill out
rivets and replace liners in accordance with instructions given in paragraph 7-72. b.
m. Inspect keyway liners for tightness. If loose, either tighten or replace rivets.
7-72. REPAIR OF MAIN WHEEL ASSEMBLY. Repairs to the main wheel assembly are limited to
blending out small nicks, scratches, gauges and areas of slight corrosion, plus the replacement of parts which
are cracked or badly corroded.
NOTE
Corrosion originates at points where the protective wheel coating
is ruptured. All traces of corrosion and residue must be removed
before wheel halves are treated and repainted. (Corrosion residue
accelerates the corrosion process.)
a. Bearing Cup Replacement:
1. Removal:
(a) Heat wheel sub-assembly in boiling water for one hour, or in an oven not exceeding
250 F(121 C) for 30 minutes.
(b) Remove sub-assembly from source of heat and remove bearing cup.
NOTE
The bearing cup should be loose enough to fall out of the bearing
bore after heating the wheel sub-assembly and inverting it. If the
cup does not drop out, tap it evenly from the bore with a fiber
drift pin.
Reissued: 9/23/80
LANDING GEAR AND BRAKE SYSTEM
2F17