25
Piston Disassembly
1.
Remove piston sleeve (243) and ‘O’ ring (242) from the
piston and discard.
2.
Press out pin (246) and remove washers (248).
3.
Pull link rod (244) apart from piston rod (241).
4.
Press out bearings (245) and (247).
Crankshaft Disassembly
1.
Bend the locking tab on tab washer (203) out of the slot in
locknut (202).
2.
Use a wooden (or fiberglass) tool handle to lock the
crankshaft. Place it through two of the cylinder ports in the
motor housing and let the crankshaft pin come to rest on it.
3.
Remove locknut (202) and tab washer (203).
4.
Press the crankshaft assembly (only, NOT bearing (204))
out through the main cavity of the motor housing.
5.
Pull bearing (204) and attached retainer ring back out,
towards adapter side of motor housing.
Disc Brake Disassembly
Refer to Dwg. MHP0947.
NOTICE
• Prior to disassembly, matchmark the cover (2), housing (6)
and support plate (19) to assist in proper alignment of parts
during reassembly.
1.
Remove brake shaft (25) and retainer ring (23). Place brake
assembly on a flat surface with cover (2) on top. Remove
elbow fitting (80) and exhaust valve (79). Alternately and
evenly loosen the two capscrews (1) until the brake spring
(17) compression has been relaxed. Remove capscrews.
2.
Remove cover (2) and diaphragm (3).
3.
Using a small tipped screwdriver or similar tool, remove
ring (4). Remove diaphragm support (5).
4.
Remove housing (6) by lifting straight away from brake
parts. Collect the three dowel pins (9) and store until
reinstallation. Inspect pins for deformation, wear and
damage. Replace if parts fail inspection.
5.
Alternately remove the six separator plates (14) and five
friction plates (13).
6.
Remove the pressure plate (15) and springs (17).
7.
Grasp the outer race (12) and remove the sprag clutch as an
assembly. Remove the spacer (11) between the sprag clutch
assembly and support plate (19).
8.
Remove gasket (18) from support plate (19). Discard
gasket.
9.
To remove the bearing (21) from the support plate (19) first
remove the retainer ring (22) and then press the bearing out
of the support plate recess.
NOTICE
• To prevent accidental damage, remove the bearing (21) only
if it requires replacement.
10. Separate the sprag clutch assembly into its component
parts. The sprag clutch assembly consists of the inner race
(10), two spacers (11), the outer race (12) and the sprag
clutch (16). The sprag clutch can be further disassembled
into two wearing plates and the sprag cage.
Automatic Drum Band Brake:
Optional feature. Refer to Dwg. MHP1281.
1.
Loosen jam nut (117) closest to plunger (114). Turn
capscrew (120) counterclockwise until disconnected from
plunger.
2.
Disconnect air line from brake cylinder (121). With the aid
of a strap wrench, remove brake cylinder (121) and
components as an assembly by turning brake cylinder
counterclockwise until disconnected from brake bracket
(106).
3.
Disconnect brake bracket (106) from band assembly by
removing three capscrews (101), spacers (102) and spacer
tubes (103). Remove spacer plate (105).
4.
Disconnect brake bracket from motor end upright (68) by
removing two capscrews (107) and two capscrews (112).
DANGER
• Springs (124) and (127) exert a considerable force on cover
(125). Extreme care must be taken when disassembling the
cylinder assembly and removing cover (125).
5.
To disassemble the cylinder (121) assembly into its
component parts conduct the following:
a.
Use a press to compress the cover (125) enough to
remove retainer ring (126). Slowly, and carefully,
relax the load exerted on cover (125) by the springs
(124) and (127). Remove cover and springs.
b.
Remove washer (128).
c.
Remove piston (123) assembly.
d.
Disassemble piston assembly into component parts by
removing retainer ring (111) and separating cylinder
rod (108) from piston (123). Remove ‘O’ rings (122),
(109) and (110). Discard ‘O’ rings.
6.
Remove plunger (114) assembly and spring (113) from
brake bracket (106).
Manual Drum Band Brake Disassembly
Refer to Dwg. MHP1372.
The winch does not have to be removed or disassembled to
disassemble the manual band brake.
CAUTION
• Release wire rope tension on the drum and disconnect main
air supply line.
1.
Raise handle (135) to free brake bands (136 and 137).
2.
Remove cotter pin (139) and pin (138).
3.
Rotate brake link stud (141) counter-clockwise until free
from brake handle.
4.
Remove grip from brake handle (135). Loosen screws in
brake handle until handle can be freed from brake band
bracket, remove brake handle. Remove pivot nut (134).
5.
Loosen capscrew (101), brake cam stop (132) will rotate to
free position.
6.
Remove cotter pin (144) and washer (142).
7.
Loosen capscrews (112).
8.
Spread brake band (137) apart slightly and slide out over
drum flange. Rotate brake band around drum and remove.
9.
Repeat this procedure for brake band (136).
10. Remove capscrews (112), washers (131), and adapter plate
(145).
11. Press bushings (143) out of brake band pivot brackets.
