TM 1-1730-232-13&P
4-17.1 Hydraulic Pump Repair (Typical - All Wheel Assembly Models) - Continued
A. REPAIR HYDRAULIC PUMP
Repair of the hydraulic pump assembly, with part number 61780, consists of disassembly and assembly New
components parts from repair kit 300487 are Installed during assembly.
1. Disassemble hydraulic pump.
CAUTION
A free floating steel ball is located under the piston assembly in the pump body. To prevent
losing or damaging the steel ball, ensure that pump body is flat on the workbench before
removing the manual control handle or piston assembly.
a. Remove retaining rings (1), straight pins (2), and detach handle assembly (3) from pump body (21).
b. Remove piston assembly (8), backup washer (9), and O-Ring (10) from pump body (21).
c. Place hand over hole in pump body, where piston assembly was just removed, and rotate pump body 180
degrees. Catch the steel ball (11) and check it for corrosion or damage
d. Remove dust protective cap (29) and gasket (30), and drain hydraulic fluid from reservoir assembly (27).
e. Remove nut (31), tie rod (28), reservoir assembly (27), and O-Ring (24).
f. Remove stick filter (23) and O-Ring (34) from pump body (21).
g. Remove pressure relief valve (22) from pump body (21).
h. Loosen setscrew (25) and remove safety release valve knob (26).
i. Unscrew safety release valve (13), backup washer (15), O-Ring (14), nylon ball (33), and ball (12) from
pump body (21).
j. Remove pipe bushing (6) and metering valve (7) from pump body (21).
k. Remove valve screw (5), copper washer (16), compression spring (17), steel ball (11), spacer (18),
compression spring (19), and steel ball (20).
I. Remove nut (41), bolt (40), and mounting plate (38) from pump body.
m. Remove nut (41), bolt (40), and hydraulic fitting guard (39) from pump body.
2. Clean hydraulic pump components.
WARNING
Dry cleaning solvent P-D-680 is toxic and flammable. Always wear protective goggles and
gloves, and use only In a well-ventilated area. Avoid contact with skin, eyes, and clothes, and
DO NOT use near open flame or excessive heat. The solvents flash point is 100°F 130°F (38°C
59°C) if you become dizzy while using cleaning solvent, immediately get fresh air and medical
help. If solvent contacts eyes, immediately flush your eyes with clean water and get medical
help.
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