Gear Door Actuating Cylinder (Wiebel Tool) - Piper Navajo Chieftain PA-31-350 Service Manual

NAVAJO CHIEFTAIN SERVICE MANUAL
6-140. DISASSEMBLY OF GEAR DOOR ACTUATING CYLINDERS. (Refer to Figure 6-26.)
a. Unlock the cylinder by applying hydraulic pressure to the clevis end (22) port. Extend piston (6)
all the way.
b.
Loosen locknut (2) and remove rod end (1) from piston (6). Remove locknut (2) from piston (6).
c. Remove safety wire (5 and 21) from nut (11) and nut (13). Loosen both nuts (11 and 13).
d. Remove end cap (4) from barrel (12) but leave end cap (4) on piston (6).
e. Remove clevis end (22) from barrel (12). Pull piston (6) with end cap (4) from barrel (12). Use
care when pulling piston out of barrel to prevent the loss of the six balls (7) which are nested in the head
end of the Piston (6).
f. Remove end cap (4) from piston (6).
g. Pull race (16), plunger (19) and spring (20) out of the clevis end (22).
h. Remove GT-ring (3) from end cap (4).
i.
Remove "O" rings (9 and 15) and the back up rings (10 and 14) from the barrel (12).
j. Remove GT-ring (8) from piston (6).
k.
Remove "O" ring (17) and back up ring (18) from plunger (19).
6-141. CLEANING, INSPECTION AND REPAIR OF GEAR DOOR ACTUATING CYLINDERS. (Refer
to Figure 6-26.)
a.
Clean the cylinder parts with a suitable solvent and dry throughly.
b. Inspect all threaded surfaces for cleanliness and for freedom of cracks and excessive wear.
c. Inspect the plunger spring (20) for evidence of breaks and distortion. Compress the spring (20) to
a length of .750 inches and measure load. Load should be 30 + 2 pounds.
d. Inspect the end cap (4), piston (6), barrel (12), race (16), plunger (19) and clevis end (22) for
cracks, chips, scratches, scoring, wear and surface irregularities which may affect proper function of the
door actuator cylinder.
e. Repair of most parts of the landing gear door actuator assembly is impractical. Replace defective
parts with new parts. Minor scratches and scores may be removed by polishing with "fine abrasive" crocus
cloth (Federal Specification P-C-458) providing their removal does not affect the operation of the actuator
assembly. Replace all "O" rings, back up rings and GT-rings with new ones during the reassembly of the
actuator.
6-142. ASSEMBLY OF GEAR DOOR ACTUATING CYLINDER. (Refer to Figure 6-26.) Lubricate all
parts with oil per MIL-H-5606 prior to assembly.
a. Install "O" ring (17) and back up ring (18) into groove of plunger (19).
b. Install nut (11) and nut (13) on barrel (12).
c. Install back up rings (10 and 14) and "O" rings (9 and 15) into grooves of barrel (12).
d. Install spring (20), plunger (19) and race (16) into clevis end (22) and secure by screwing barrel
(12) into clevis end (22). Tighten barrel down against the race (16), and torque to 120 to 140 inch-pounds.
Then tighten nut (13) against the clevis end (22) and torque to 120 to 140 inch -pounds.
e.
Install GT-ring (8) into groove of piston (6).
f.
Install GT-ring (3) into groove inside the end cap (4).
g. Slide piston (6) into the end cap (4), install six bails (7) into holes in piston head (6) and insert
assembly into bore of barrel (12). Screw end cap (4) onto barrel (12) and align port in end cap (4) with
port in clevis end (22). Tighten nut (11) against end cap (4) and torque to 120 to 140 inch-pounds
h. Secure nut (1 1) to end cap (4) using safety wire (5).
i. Secure nut (13) to clevis end (22) using safety wire (21).
j. Install locknut (2) and rod end (1) on piston (6).
k. Adjust rod end (1) to achieve proper length of actuator assembly and lock with locknut (2).
6-143. INSTALLATION OF GEAR DOOR ACTUATING CYLINDER. (Same as Paragraph 6-137.)
Reissued: 9/23/80
2D2
HYDRAULIC SYSTEM