TM 5-3810-294-34
9. Shim
1. Cotter pin
10. Shim
2. Nut
11. Bearing
3. Coupling flange
12. Key
4. Nut (6)
13. Worm shaft
5. Lockwasher (6)
14. Bearing 2)
6. Oil seal
15. Worm sleeve
7. Retainer
6. Gasket
8. Shim
5-18. Inspection and Repair
b. Install shaft and bearings into worm sleeve
Inspect worm shaft for signs of excessive wear or thread
(15). Make sure bearings (14) are firmly against the inner
damage. Clean all parts in a suitable solvent. Discard
shoulder in the worm sleeve, as shown in the insert.
gasket (16, fig. 5-6) shims (8, 9, and 10) unless shims
c. Install oil seal (6) into retainer (7). Be sure sealing
are in very good condition. Be sure to replace with the
surface of shaft (13) is clean and free from burrs, and that
same measured thickness of shims which 'were
seal (6) wiper lip points inward, toward worm portion of shaft
removed, because these shims determine the shaft end
(13).
clearance. End clearance should be maintained at 0.003
d. Install gasket (16) over studs on the chain case on
to 0.005 inch. Replace bearings unless replacement
which worm sleeve (15) is mounted. Install shims (8, 9, and
bearings are not available. Clean key (12) with a fine file,
10) on the face of worm sleeve (15), and place retainer (7) in
if necessary, and be sure the key is a snug fit in shaft
the bore of sleeve (15).
(13) keyway. Replace any part in doubtful condition.
e. Install key (12) and flange (3) and secure entire
5-19. Reassembly
assembly with nut (2) and cotter pin (1).
Refer to figure 5-6 and assemble the worm shaft as
5-20. Installation
follows:
a. Preheat bearing (11 and 14) and install bearings on
The adjustment of the worm to worm wheel contact area is
proper ends of shaft (13). Bearings (14) are thrust
described in paragraphs 2-19 and 2-20.
bearings and must be assembled so that the thrust is
absorbed in proper direction. Figure 5-6 shows how to
install the bearings.
Section IV. REPAIR OF BOOM HOIST SHAFT
5-21. Description
clean all parts using a suitable solvent. Replace all O-rings,
The boom hoist shaft is worm gear driven by a propeller
seals, bearings, gaskets, deformed shims, and other
shaft and worm gear coupled to the transmission output
expendable parts. Inspect all parts for wear, scoring, cracks,
shaft (refer to fig. 5-1). The shaft drives the rear
or any other visible signs of damage, and replace any part no
drumshaft assembly by means of a roller chain-drive
in good condition. Inspect the parts listed in table 1-2 for
sprocket arrangement from the left end of the shaft. The
conformity with maximum clearances and replace any part
boom hoist drum is mounted on the right end of the
worn beyond the maximum dimensions listed. Adjust end
shaft. The boom both lifted and lowered under power by
play by shimming, if necessary and maintain the tolerances
a planetary gear arrangement located in the boom hoist
listed.
drum.
5-24. Reassembly and Installation
5-22. Removal and Disassembly
The boom hoist shaft is reassembled as it is installed into the
The boom hoist shaft must be disassembled remove it.
machine (refer to para 2-20). Do not attempt to assemble the
boom hoist shaft and then install it.
assembly.
5-23. Inspection and Repair
When the boom hoist shaft has been disassembled.
5-13