TM 9-2320-272-24-2
4-21. ENGINE OIL PUMP REPLACEMENT
THIS TASK COVERS:
c. Installation
a. Gear Backlash Test
b. Removal
INITIAL SETUP:
REFERENCES (TM)
APPLICABLE MODELS
TM 9-2320-272-24P
M939/A1
EQUIPMENT CONDlTlON
TOOLS
l Engine oil filter removed (para. 3-5).
General mechanic's tool kit (Appendix E, Item 1)
l Engine front gearcase cover removed (task a. only)
Dial indicator (Appendix E, Item 36)
Torque wrench (Appendix E, Item 144)
MATERIALS/PARTS
Oil pump flange gasket (Appendix D, Item 176)
Six lockwashers (Appendix D, Item 354)
Two lockwashers (Appendix D, Item 411)
Two lockwashers (Appendix D, Item 382)
1.
Place dial indicator on engine block flange (2). Ensure anvil is positioned against drive gear
tooth (1). Turn drive gear (3) clockwise until tight.
2.
Zero-dial indicator index line and turn drive gear (3) counterclockwise until tight. Note amount of
movement of dial indicator hand. Normal range of movement is 0.004-0.016 in. (0.10-0.40 mm).
Replace drive gear (3) if less than 0.002 in. (0.05 mm).
CAUTION
Mounting and assembly screws are of different sizes and lengths.
Screws must be tagged for installation. Misplaced screws can
damage parts.
1.
Remove two screws (8) and lockwashers (7) from oil pump body flange (16). Discard lockwashers (7).
2.
Completely loosen screw (13) and lockwasher (15) from oil pump body flange (16). Screw (13) is
removed during next step. Discard lockwasher (15).
3.
Remove screws (6) and (10) and lockwashers (5) and (11) from filter head (9). Discard
lockwashers (5) and (11).
4.
Remove oil pump (12) and gasket (4) from front gearcase (14). Discard gasket (4) and clean gasket
remains from mating surfaces of oil pump (12) and front gearcase (14).
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