TM 9-2320-272-24-2
4-18. FRONT GEARCASE COVER MAINTENANCE (Contd)
c . Cleaning and Inspection
Clean gearcase cover (1) (para. 2-7).
1.
Remove all gasket material from mating surfaces on gearcase cover (1).
2.
Inspect gearcase cover (1) (para. 2-8). Replace gearcase cover (1) if any defect is noted.
3.
Using surface plate, lap gasket mating surfaces to remove high and low area to ensure flatness and
4.
good sealing.
Check seal bores (5) and (6) for nicks, burrs, and gouges. Small nicks, burrs, and gouges can be
5.
smoothed out with crocus cloth.
Check bushing (7) in seal bore (6) for scoring and pitting. Discard bushing (7) if scored or pitted.
6.
Check bushing (7) for wear using inside micrometer. Discard bushing (7) if inside diameter is more
7.
than 1.571 in. (39.90 mm).
Measure outside diameter of accessory driveshaft. Bushing-to-driveshaft clearance must be between
8.
0.003 and 0.007 in. (0.08 and 0.18 mm). Use undersize bushings to obtain proper clearance.
Inspect bushing (8) for cracks or scoring. Replace bushing (8) if cracked or scored.
9.
Measure bushing (8) outside diameter. If less than 4.745 in. (12.52 mm), replace bushing (8).
10.
Inspect two dowel pins (3) in engine block (4) for cracks, breaks, or burrs. Replace dowel pins (3) if
11.
cracked or broken. Repair if burred (para. 2-9).
Inspect two dowel pin holes (2) in gearcase cover (1) for elongated holes. Replace gearcase cover (1)
12.
if holes are elongated.
d. Assembly
NOTE
Do not perform steps 1 through 3 unless installing new bushings.
1.
Using arbor press and mandrel, remove bushing (7) from gearcase cover (1) and install new
bushing (7) in gearcase cover (1).
2.
Using puller, remove bushing (8) from gearcase cover (1).
3.
Cut new bushing (8) with outside diameter 4.747-4.750 in. (120.57-120.65 mm). Using arbor press
and mandrel, install bushing (8) on gearcase cover (1) with chamfer edge of bushing (8) toward
gearcase cover (1).
NOTE
l Do not install mandatory replacement oil seals until gearcase
cover is to be reassembled to engine. This prevents collection of
dirt.
l Lightly coat all contacting parts of shafts, seals, and O-ring
with lubricating oil before installation.
4.
Using proper oil seal installation tool, install new oil seals (9) and (10) in gearcase cover (1).
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