Disassembly Of Time Delay Check Valve; Assembly Of Time Delay Check Valve; Installation And Adjustment Of Inboard Gear Doors Switch; Power Pack Bench Test Adjustment - Piper Cheyenne IIIA Airplane Maintenance Manual

PIPER AIRCRAFT
PA42-720 (Advanced Trainer)
MAINTENANCE MANUAL
A. Main (continued)
54. Disassembly of Time Delay Check Valve. (Figure 403, Item 59)
(a) Remove check valve body from power pack body.
(b) Remove snap ring.
(c) Using brass hook, pull out seat.
(d) Remove ball and spring.
55. Assembly of Time Delay Check Valve. (Figure 403, Item 59)
(a) Install spring and ball into check valve body.
(b) Lubricate and install O-ring on seat.
(c) Install seat into check valve body and secure with snap ring.
(d) Lubricate threads and install O-ring on valve body. Install assembly into power pack body and
torque to 45 inch-pounds.
56. Installation and Adjustment of Inboard Gear Doors Switch.
(a) Install switch assembly with insulating plate between the switch and manifold. Secure lightly
with washers and screws.
(b) Move selector spool to gear up and down position a few times to ensure proper actuating of
switch from ON to OFF. Torque switch screws to 20 inch-pounds.
(c) Safety wire solenoid to bracket (Figure 404) using 0.032 inch safety wire.
(d) Connect electrical wires from switch to terminal block (Figure 403). Secure to solenoid with
plastic strap.
NOTE: Electrical wires are color coded and must be matched when reinstalling wires.
(e) Install plungers, springs, and button into handle release bodies. Retain with snap rings.
(f) Install handle release assemblies loosely in body.
57. Power Pack Bench Test Adjustment.
After completion of overhaul, bench test power pack prior to installation in airplane using hydraulic
test unit or similar test equipment.
(a) Use only clean hydraulic fluid per MIL-H-5606.
(b) Equipment needed is as follows:
(1.) Test unit pump and hand pump with 2500 psi capacity.
(2.) One hydraulic pressure gauge with 2500 psi capacity.
(3.) One hydraulic pressure gauge with 200 psi capacity.
(c) Connect test pressure hose to pressure inlet port of power pack. The 2500 psi gauge must
operate off pressure line.
(d) Connect suction hose to suction port of power pack.
(e) Connect vent hose (if included) to vent port at top of reservoir-cover.
(f) Cap all other fittings with high pressure caps.
NOTE: For control of door valve solenoid, fabricate an electric harness (Figure 502). This
harness, when connected to 24-volt battery, allows control of electrical current to door
valve solenoid permitting hydraulic door circuits to operate.
EFFECTIVITY:
040-999
Jan
10/9029-10-00