8
Form MHD56332 Edition 1
5. To remove connecting rods (459) from crankshaft (473), take out setscrew (478)
and drive out taper pin (479) securing counterbalance to crankshaft.
6. Loosen capscrew (480), remove counterbalance, then pull off connecting rod
rings (474), connecting rods (459), bushing (476) and sleeve (475).
Live Air Throttle Valve
Refer to Dwg. MHP0203.
Match mark throttle valve parts to ensure proper reassembly.
1. Remove pins (428) and tap out pin (429) from handle bracket (426).
2. Mark the square end on valve body (441) and handle (426) to ensure correct
orientation during reassembly. Remove handle assembly.
3. Make note on how spring (427) is positioned before removing it. Remove
capscrews (444), lockwashers (443) and exhaust cover (442) from housing
(438).
4. Remove pipe plug (434), spring (422), poppet valve (436) and ball (421) from
housing (438). Pull valve (441) out of valve bushing (440).
5. Check parts for score marks or wear. Clearance between valve bushing (440)and
valve (441) should not exceed 0.002 in. (0.05 mm) or excessive air leakage will
occur.
Manual or Automatic Band Brake
Refer to Dwg. MHP0209.
1. Automatic Brake:
a.
Disconnect and remove hose, fittings and dump valve (112) from cylinder
(110).
b.
Remove cotter pin (102) and pin (101) from link stud (103) and brake band
(128).
c.
Remove cotter pin (102) and pin (106). Separate clevis (107) from brake
lever (105).
d.
Remove cotter pin (102) and pin (117). Remove cylinder (110) from bracket
(118).
2. Manual Brake:
a.
Remove cotter pin (102) and pin (101) from handle (104) then remove
handle (104) from brake band (128).
3. Remove capscrews (45), lockwashers (119) and stop plate (126). Ensure pivot
bracket (122) is no longer secured to siderail.
4. Use a hoist to raise winch approximately 6 inches (15 cm). Separate brake band
(128) halves and rotate brake band assembly slowly until it can be removed from
drum (80).
5. Remove cotter pins (102) and pins (121) so brake band halves (128) can be
removed from arm (124). Lower winch when brake band assembly has been
removed.
6. Refer to Product Parts Information Manual to order replacement parts.
Reduction Gear
NOTICE
• It is important to maintain a clean work area when reduction gear assembly
is disassembled.
• Disassembly is not recommended, if it is unavoidable, use the following
steps.
Refer to Dwg. MHP2773.
1. Place the reduction gear assembly on a clean work bench such that the end
containing seal (43) is down.
2. Remove capscrews (75) and pry off cover (73).
3. Remove four pins (74) from between cover (73) and spacer (71) and store in a
safe place.
4. Remove ring gear (72), sun gear (69) and planet assembly (67).
5. Remove ring gear (63) and spacer (71). Remove and discard ‘O’ rings (51) and
(62) from ring gears (63) and (72).
6. Remove capscrews (60) from the input housing (59).
7. Lift off input housing (59) and remove sun gear (66) from planet assembly (67).
8. If required, remove thrust plate (55) from sun gear (66).
9. Remove planet assembly (58) and sun gear (56).
10. Remove planet assembly (54) and ring gear (53).
11. Remove three dowel pins (52) from gear carrier (47) and store in a safe place.
12. Remove and discard ‘O’ rings (51) from ring gear (53).
13. Remove retainer ring (50) and bearing (49) from gear carrier (47).
Cleaning, Inspection and Repair
Cleaning
Clean all winch component parts in solvent (except drum brake bands and disc brake
friction plates). The use of a stiff bristle brush will facilitate removal of accumulated
dirt and sediments in the reduction assembly, on housings, frame and drum. If drum
bushings have been removed it may be necessary to scrape old Loctite® from drum
bushing bores. Dry each part using low pressure, filtered compressed air. Clean drum
brake band using a wire brush or emery cloth. Do not wash drum brake band in
solvent. If drum brake band lining is oil soaked, it must be replaced.
Inspection
All disassembled parts should be inspected to determine their fitness for continued
use. Pay particular attention to the following:
1. Inspect all gears for worn, cracked, or broken teeth.
2. Inspect all bushings for wear, scoring, or galling.
3. Inspect shafts for ridges caused by wear. If ridges caused by wear are apparent
on shafts, replace shaft. Inspect all surfaces on which oil seal lips seat.
4. Inspect all bearings for play, distorted races, pitting and roller or ball wear or
damage. Inspect bearings for freedom of rotation.
5. Inspect all threaded items and replace those having damaged threads.
6. Inspect drum band brake lining for oil, grease and glazing. If drum band brake
lining is oil-soaked replace brake bands as a set. Remove glazed areas of band
brake lining by sanding lightly with a fine grit emery cloth.
7. Measure thickness of band brake lining. If brake band linings are less than 0.062
inch (2 mm) thick anywhere along edges replace brake bands (128) as a set.
8. Inspect cylinder bores. Minor scratches in bore lining may be repaired by lightly
honing to remove. Refer to tolerances listed below for acceptable clearances.
Replace liner if deep scratches or gouges are apparent. Measure inside diameter
of liner. If measurement is greater than 4.764 inches (121 mm) replace liner.
‘Ring Gap’ may also be used to determine wear; place compression ring into liner,
using a piston, push ring until approximately half way in liner and measure
‘Gap’— 0.003 inch (0.076 mm) is normal; replace rings, or liner, if ‘Gap’ exceeds
0.020 inch (0.51 mm).
9. Inspect drive plates for warpage or other damage, and replace damaged parts as
necessary. Replace input pinion shaft oil seal.
10. Measure thickness of brake friction disc. Friction disc must show an even wear
pattern. If friction disc is 0.076 in. (1.93 mm) or less, replace disc.
Repair
Actual repairs are limited to removal of small burrs and other minor surface
imperfections from gears and shafts. Use a fine stone or emery cloth for this work.
Do not use steel wool.
1. Worn or damaged parts must be replaced. Refer to the applicable Parts Listing for
specific replacement parts information.
2. Inspect all remaining parts for evidence of damage. Replace or repair any part
which is in questionable condition. Cost of the part is often minor in comparison
with cost of redoing the job.
3. Smooth out all nicks, burrs, or galled spots on shafts, bores, pins, or bushings.
4. Examine all gear teeth carefully, and remove nicks or burrs.
5. Polish edges of all shaft shoulders to remove small nicks which may have been
caused during handling.
6. Remove all nicks and burrs caused by lockwashers.
7. Replace all gaskets, oil seals, and ‘O’ rings removed during winch disassembly.
Assembly
General Instructions
-
Use all new gaskets and seals.
-
Replace worn parts.
-
Assemble parts using match marks attached during disassembly. Compare
replacement parts with originals to identify installation alignments.
-
Lubricate all internal parts with rust and oxidation inhibiting lubricant, ISO
VG100 (SAE 30W).
-
Apply a light coat of Loctite® 243 to all threaded components prior to
assembly, unless otherwise specified.
Live Air Throttle Valve
Refer to Dwg. MHP0203.
NOTICE
During assembly align parts using match marks made during disassembly.
1. Install valve (441) and valve bushing (440) into the housing (438).
2. Install ball (421), poppet valve (436), spring (422) and pipe plug (434) in
housing(438).
3. If screws (430) were removed during disassembly, reinstall in housing (438) and
handle bracket (426).
4. Place spring (422) and ball (421) in handle bracket (426).
5. Depress spring and ball with handle (420) and install pin (425) with washers
(424)and pins (423). Bend pin (423) apart.
6. Install spring (427) and handle assembly on square shaft of valve (441) taking
note of the match marks put on during disassembly. The ends of the spring
(427)must straddle the screw (430) on handle bracket (426). Secure handle
assembly to valve with pins (429) and (428). Install sleeves (432) and capscrews
(431) on housing (438). Attach exhaust cover (442) to housing (438) with
capscrews (444)and lockwashers (443).
7. Check throttle handle moves fully left and right without sticking or binding.
Throttle handle should center, by spring force, automatically when released.
Motor
Refer to Dwg. MHP0210.
1. Press bearing (465) onto crankshaft counterbalance. Place connecting rods (459)
on bushing (476) and hold them in place with the two connecting rod rings
