ARMY TM 9-6115-670-14&P
6-33
6.14. IDLE GEAR BUSHING.
This task covers: a. Test
b. Replace
INITIAL SETUP
Tools
General Mechanic's Tool Kit
(Item 1, Appendix B)
Inside Micrometer Caliper
(Item 42, Appendix B)
Outside Micrometer Caliper
(Item 43, Appendix B)
Idle Gear Bushing Replacing Tool
(Item 18, Appendix B)
Equipment Conditions
Gear case removed (para 6.12.).
Materials/Parts
Idle Gear
TEST
a. Refer to Figure 6-11 and use inside micrometer caliper to measure the ID of idle gear bushing.
It should measure between 0.78740 and 0.78941 in. (20 and 20.051 mm).
b. Use outside micrometer caliper to measure the OD of idle gear shaft. It should measure
between 0.78610 and 0.78661 in. (19.967 and 19.980 mm).
c. Calculate oil clearance between idle gear bushing and idle gear. It should be between 0.00079
and 0.00331 in. (0.020 and 0.084 mm).
d. If oil clearance exceeds allowable limit, replace bushing and retest oil clearance.
e. If oil clearance still exceeds allowable limit, replace idle gear shaft (para 6.15.).
REPLACE
a. Refer to Figure 6-11 and use idle gear bushing replacing tool to press idle gear bushing out
from idle gear.
b. Use idle gear bushing tool to install idle gear bushing in idle gear. Leave 0 to 0.0079 in. (0 to
0.2 mm) clearance between ends of idle gear bushing and idle gear.
