ARMY TM 9-2815-255-24
AIR FORCE TO 38G1-95-2
MARINE CORPS TM 2815-24/4
3-41. BALANCER SHAFTS AND BUSHINGS.
Remove timing gear cover, refer to paragraph 3-39.1.
Remove lower idler gear, refer to paragraph 3-42.1.
Remove oil pump gear, refer to paragraph 3-21.1.
Measure balancer shaft end play, refer to paragraph 3-41.2.
Remove two capscrews (7, FIGURE 3-108) and lockwashers (8) securing each thrust plate (9 and 10); remove
thrust plates (9 and 10). Discard lockwashers.
During removal, Identify left and right balancer shafts (13 and 14) for correct assembly. Journals
are lapped for one direction of rotation and Interchanging shaft locations could cause premature
wear of shafts and bushings.
Remove balancer shafts (13 and 14).
If necessary, remove gear (11 or 12) from balancer shaft (13 or 14) using an arbor press and gear puller.
Remove key (15) from shaft.
If necessary, use balancer shaft bushing driver (JD-249) and drive bushings (16) out of engine block.
3-41.2. Inspect and Measure.
Use a dial indicator and measure balancer shaft end play. New balancer shaft end play is 0.002 to 0.010 inch
(0.05 to 0.26 mm). Maximum allowable end play is 0.015 inch (0.38 mm).
If end play of balancer shafts exceeds specifications, then check thickness of thrust plate as this
determines end play. Refer to step d.
With bushings (16, FIGURE 3-108) removed, check for cracked or broken block bosses.
Inspect for broken, cracked, or excessively worn gears (11 and 12).
Check thrust plates (9 and 10) for scoring or other excessive wear. New thrust plate thickness is 0.117 to. 0.119
inch (2.97 to 3.02 mm).
Inspect bushings (16) in engine block for wear or damage.
Measure balancer shaft bushing (16) ID.
New standard bushing diameter is 1.5030 to 1.5054 inches (38.177 to 38.237
New oversize bushing diameter is 1.5035 to 1.5045 inches (38.194 to 38.220
Measure balancer shaft journal diameter. New part diameter is 1.5014 to 1.5024 inches (38.137 to 38.163 mm).
Subtract journal diameter from bushing diameter. New part oil clearance is 0.001 to 0.004 inch (0.02 to 0.10
mm). Maximum allowable oil clearance is 0.006 inch (0.15 mm)
Install new bushings (16) and/or a new balancer shaft (13 or 14) if oil clearance is not within specification.
Oversize bushings are available. If used, engine block must be line bored to 1.7015 to 1.7025
inches (43.237 to 43.263 mm), refer to paragraph 3-41.3.