Piper Navajo PA-31 Service Manual page 358

PIPER NAVAJO SERVICE MANUAL
CAUTION
It is very important that the hand pump be operated very slowly
as pressure is being increased to bleed the hand pump relief valve.
If the hand pump is operated rapidly, damage to the valve can
occur as air permits parts to "slam" against each other.
Maximum indication of the gauge should be as indicated in Table VI-I. During the pumping operation,
the emergency hand pump should not feel spongy in either the up or down stroke.
e. Crack door-open fitting to release gauge pressure. Remove the gauge cap door-open fitting. and
drain the fluid from reservoir.
6-116. HAND PUMP (EMERGENCY) (WIEBEL TOOL).
6-117. REMOVAL OF HAND PUMP. (Same as Paragraph 6-109.)
6-118. DISASSEMBLY OF HAND PUMP. (Refer to Figure 6-27.)
a. To remove the plunger (13) and component parts, remove quick click pin (14) and the four
screws (25) allowing the bracket (21) to separate from the pump body (6).
NOTE
To remove the quick click pins (14), (22) and (24), use a hollow
steel rod having an outside diameter of .186-.184 inches and an
inside diameter (bore) of .166 inches. The inside diameter should
have a minimum depth of .125 inches.
b. Pull the plunger assembly from the pump body.
c. Slide the scraper (20) and the gland (16) from the plunger (13).
d.
To remove the check valve assembly from the plunger, remove the snap ring (7) from the plunger
cavity and with a low charge of air injected into the hole in the side of the plunger, remove the seat (9), ball
(10) and the spring (11).
e. To remove the check valve assembly located in the suction port of the pump body (6) remove the
snap ring (1). Inject a low charge of air into the plunger bore in the pump body to remove the seat (3), the
ball (4) and the spring (5).
6-119. CLEANING, INSPECTION AND REPAIR OF HAND PUMP. (Same as Paragraph 6-111.)
6-120. ASSEMBLY OF HAND PUMP. (Refer to Figure 6-27.) Lubricate all parts with oil per MIL-H-5606
prior to assembly.
a. Lubricate "O" ring (8) and install on seat (9).
b. Install spring (11), ball (10) and lubricated seat (9) into the plunger (13) and retain with snap
ring (7).
c. Install GT-ring (12) on the plunger (13).
d. Install "O" ring (19) and back up (17) into inside groove of gland (16).
e. Install "O" ring (15) and back up (18) into outside groove of gland (16).
f. Lubricate the complete gland (16) and slide onto the plunger (13) with the recessed end on the
outside.
g. Lubricate the bore of the pump body (6) and slide plunger (13) with gland (16) into the pump
body (6).
h. Install the scraper (20) into the recess of gland (16) by sliding scraper over plunger (13). Tapered
lip of scraper (20) to face outward.
Revised: 10/12/83
HYDRAULIC SYSTEM
2D4