pin (9) out of boom and remove gear and sprocket (7).
(11)
Press sleeve bearing (8) out of gear and
sprocket (7).
b. Cleaning, Inspection, and Repair.
(1)
Clean all parts and dry thoroughly.
(2)
Inspect pins and shafts for excessive
wear, out-of-round, or other damage. Inspect gears and
sprockets for worn, bent, or chipped teeth. Inspect
hardware for burs or stripped threads.
(3)
Repair by replacing damaged or
defective parts or mounting hardware.
c. Reassembly and Installation. Reassemble and
install crowd and retract mechanism by reversing
procedures in a above.
6-5. Chain Tightener
a. Removal and Installation.
(1) Remove crowd chain (1, fig. 6-4) from digging
drum sprocket (TM 5-3810-201-12).
(2) Remove cotterpins (10) and pin (11) from yoke
(15) and revolving frame.
(3) Remove two capscrew (9), lockwasher (8), and
lockplate (7) from clevis (14).
(4) Remove pin (4) from yoke (15) and clevis (14),
then remove roller (2) and sleeve bearing (8).
(5) Remove fitting (6) from bushing (5), then remove
bushing from pin (4).
(6) Remove bottom nut (13) from clevis (14),
unscrew clevis from pin (12), then remove remaining nut
Figure 6-3. Crowd and retract mechanism, exploded
(13) from clevis (14).
view.
(3) Remove shaft (6) and sprocket (2) from yoke
(7) Remove pin (12) from revolving frame.
(6).
b. Cleaning, Inspection, and Repair.
(4) Press sleeve bearing (1) out of sprocket (2).
(1) Clean all parts and dry thoroughly.
(5) Remove crowd and retract gear guard (TM 5-
(2) Inspect pins and sleeve bearing for scoring or
3810-201-12).
excessive wear. Inspect yoke and clevis for bends,
cracks, breaks, or excessive wear. Inspect roller for
(6) Remove two nuts (10), lockwashers (12),
excessive wear.
capscrew (14), and collar (18) from shaft (17).
(3) Repair worn or cracked roller by building up with
weld, then grinding to size. Weld all cracks or breaks in
(7) Use a gear puller and remove shaft (17) from left
yoke or clevis, or replace defective components. Replace
side of boom, removing gear (15) and sprocket (16) as
defective mounting hardware. Replace worn pins and
shaft (17) is pulled from them.
(8) Press sleeve bearings (11) from boom foot.
c. Reassembly and Installation.
(9) Remove fittings (4) from shafts (5), sprocket (2),
(1) Reassemble and install by reversing procedures
and boom.
in a above.
(10) Remove two bolts (20), lockwasher (19), keeper
(2) Adjust crowd and retract chain (TM 5 3810-201-
plate (18), and pin (9), then drive
12).
AGO 20051A
6-4
