Main Gear Actuating Cylinder Disassembly; Main Gear Actuating Cylinder Cleaning, Inspection And Repair; Main Gear Actuating Cylinder Assembly; Main Gear Actuating Cylinder Installation - Piper PA-44-180 SEMINOLE Maintenance Manual

DISASSEMBLY OF MAIN GEAR ACTUATING CYLINDER. (Refer to Figure 29-7.)
1. With the cylinder removed from the airplane, push the piston rod (by hand) toward the clevis to
remove oil from the unit.
2. Put clevis in a soft jaw vise and clamp against the clevis bearing.
3. If no pipe fitting is installed in the port of the end gland, install a fitting (1/8 - 27) into the port. This
fitting need not be tight as it will be used for leverage only.
4. Rotate the gland counterclockwise (with use of fitting) until the end of the gland lock ring shows in the
slot in the cylinder body. Reverse rotation of the gland (clockwise direction) to allow the lock ring to
move out of the slot. (Refer to Figure 29-8.) (It may be necessary to give the ring an assist to start out
of the slot. If so, insert a strong wire pick or other available tool in the slot to lift up the end of the ring
and then rotate gland.)
5. Pull the piston and end gland from the cylinder.
6. Remove O-rings as desired.
CLEANING, INSPECTION AND REPAIR OF MAIN GEAR ACTUATING CYLINDER.
1. Clean the cylinder parts with a suitable dry type solvent and dry thoroughly.
2. Inspect the cylinder assembly for the following:
A. Interior walls of cylinder and exterior surfaces of piston for scratches, burrs, corrosion, etc.
B. Threaded areas for damage.
C. End fitting retainer slot for excess wear.
D. Rod end fitting and swivel fitting of cylinder for wear and corrosion.
3. Repairs to the cylinder are limited to polishing out small scratches, burrs, etc., and replacing compo-
nents. (Refer to Parts Catalog for replacement part numbers.)
ASSEMBLY OF MAIN GEAR ACTUATING CYLINDER. (Refer to Figure 29-7.)
1. Install O-ring on the exterior of the end gland.
2. Install O-ring and back-up ring in the interior of the end gland.
3. Install O-ring on the body of the piston assembly.
4. Lubricate the areas around the O-rings with hydraulic fluid, park-o-lube or vaseline; slide the end
gland on the piston rod and the piston into the cylinder housing.
5. Insert the hook end of a new lock ring (P/N 755 997) in the slot in the cylinder body and slot in the end
gland. Rotate gland counterclockwise to completely wrap lock wing into assembly.
6. Align port in end gland and cylinder body.
7. Check smoothness of operation of piston and static pressure test unit to check for possible cut O-rings.
INSTALLATION OF MAIN GEAR ACTUATING CYLINDER.
1. Attach the cylinder to its attachment fitting in the wheel well using bolt and nut.
2 . Attach the operating rod end and downlock spring swivel fitting to the upper side brace retraction fitting
by using bolt, washer and nut. Ascertain swivel fitting is free to rotate.
3. Connect the downlock spring to the swivel fitting.
4 . Check the adjustment of the cylinder rod end. (Refer to Adjustment of Main Landing Gear, Chapter 32.)
5. Operate pump to purge system of air and check fluid level in reservoir.
6. Turn master switch ON. Ensure the three green GEAR DOWN and LOCKED lights or ON. Turn
switch OFF. Remove the airplane from jacks.
PIPER AIRCRAFT
PA - 4 4 - 1 8 0 / 1 8 0 T
AIRPLANE MAINTENANCE MANUAL
2C21
29-13-05
Page 29-26
Revised: June 20, 1995