BOOM HOIST PAWLS
SUBSECTION 8F
4. Inspect the boom hoist brake linings and reline if neces-
5. Remove the upper deck panel immediately to the right of
sary. See Subsection 8C.
the access door. This makes access to the boom hoist pawls
easier.
5. Inspect the boom hoist planetary brake linings and re-
line if necessary. See Subsection 8C.
NOTE
6. Inspect cables (31 and 32) for condition. Check for free-
If necessary, remove the shroud between the boom
dom of movement.
hoist drum and the right hoist drum.
7. Check the condition of springs (24) which are mounted
6. Release the tension in springs (17) by loosening jam nuts
towards the inside of the pawls. Replace as required.
(20). Remove springs (17) from (21). Remove pin (21) from
the band lever.
ASSEMBLY. To assemble the boom hoist pawls and oper-
ating mechanism, proceed as follows (see Figure 8F-2):
7. Loosen brake band adjusting bolts (10 and 77). Do not re-
move nuts (07 and 74). This will reduce the binding tension
1. Place cylinder (41) into the cylinder support and secure
of the brake operating mechanisms on pin (57).
in place with the attaching hardware.
8. Disengage boom hoist pawls (53 and 56) from the
2. Place push rod (36) into support bracket (46) and insert
ratchets, as follows:
spring (37) on the push rod. Thread spring guide (38) and
nut (40) on the push rod.
A. Remove pins (22 and 45) to release the tension in cables
(31 and 32).
3. Install pins (22, 35 and 49). Adjustment to the springs
and operating mechanism are made later. Connect spring
B. Disengage pawls (53 and 56) from the drum ratchets.
(39) to lever (50) and the spring bracket on support bracket
9. Remove capscrew (62) from bracket (51) and remove rod
(46).
end (61) from pin (57).
NOTE
Pawls (53 and 56) are similar and are assembled in
the same manner.
4. Install pawls (53 and 56) on cables (31 and 32). Install
The next step in this procedure involves re-
spring seats (28). springs (29) and stop nuts (26) on cables
moving pin (57) from the pawls. When remov-
(31 and 32).
ing pin (57) the drum brake operating mechan-
INSTALLATION. To install the boom hoist pawls, proceedas
ism should be supported so it will not fall.
follows (see Figure 8F-2):
10. Slowly pull the pin out of the drum brake operating
mechanism, out of the two pawls, and stop.
NOTE
NOTE
If only pawl (56) was removed, proceed to step 3.
If only planetary pawl (56) must be removed, pull pin
1. Place pawl assembly (53) up to pin (57). Push the pin
through the pawl and bracket (52).
(57) out only the distance necessary to remove the
planetary pawl.
2. Align the boom hoist brake and push pin (57) through it
into bracket (55).
11. Remove nuts (26), spring seats (28). and springs (29).
Then remove pawls (53 and 56).
3. Place spacer (01) and pawl assembly (56) up to pin (57).
Push the pin through the spacer, the pawl and into the sup-
DISASSEMBLY. To disassemble the pawl operating mech-
port receptacle on the revolving frame.
anism and to remove the pawl cylinder, proceed as follows
(see Figure 8F-2):
4. Insert rod end (61) into pin (57) and secure with cap-
screw (62) to bracket (51).
1. If cylinder (41) must be removed, loosen jam nut (40) and
remove spring (39). Remove pins (22, 35 and 49) and re-
5. Install pin (21) in the planetary brake band lever and at-
move push rod (36), spring (37), spring guide (38) and nut
tach springs (17), studs (18), washers (19) and nuts (20).
(40).
6. Remove the caps and plugs from all hydraulic lines and
2. Remove cylinder (41) by removing capscrew (44) and
connections. Install the hydraulic lines.
lockwasher (43).
7. Bleed the hydraulic cylinders to remove any air trapped
INSPECTION AND REPAIR. Prior to assembly, the follow-
in the hydraulic lines. See the bleeding procedure in Sub-
ing items should be Inspected (see Figure 8F-2):
section 5A.
1. If either pawl is worn, cracked or broken, replace the
8. Move the boom hoist lever forward to compress spring
pawl.
(79). Pull assembly pin (71) out of brackets (65 and 70).
Place the boom hoist lever back to neutral.
2. If the cylinder leaks or has been performing erratically,
remove and overhaul. See Subsection 5D.
9 See Subsection 8C and adjust the boom hoist brakes.
3. Inspect the boom hoist drum ratchets for wear, cracks or
10. See SubsectIon 8C and adjust the boom hoist plane-
broken teeth. Repair or replace if necessary. See Subsec-
tary brakes.
tion 8B.
8F-2
