SUBSECTION 6E
SWING BRAKES AND LOCKS
GENERAL
This subsection contains the information necessary to re-
move, repair, install and adjust the swing brake.
SWING BRAKE (2100J992-4)
GENERAL. The swing brake is located at the left side of the
upper. The pinion of the swing brake shaft is engaged in the
ring gear. The brake is of the spring set-hydraulically
released type. The purpose of the swing brake is to lock the
upper in position in relation to the carrier, while traveling,
working, or moving to a new location. It is not intended or
designed to stop the upper from swinging at the end of each
swing cycle or as a control regularly used in operating the
machine. It is more accurately described as a "locking"
brake.
When the operator moves the swing brake control switch to
release the swing brake, hydraulic pressure is applied to the
cylinder which extends a piston to release the brake. When
the operator moves the swing brake control switch to en-
gage the swing brake, hydraulic pressure is released from
the cylinder, retracting the piston which allows a spring to
set the brake.
The length of the operating springs with the brakes applied
Figure 6E-1. Swing Brake Adjustment
(hydraulic pressure released to the cylinder) should be 4-
1/4 inches when in proper adjustment (see Figure 6E-1).
The swing brake shoes should be replaced if the shoes be-
come cracked, warped, scored or otherwise unserviceable.
Proper swing brake use results in very little shoe wear, thus
INSPECTION AND REPAIR. Prior to assembly, all swing
shoes seldom "wear" out.
brake parts should be inspected as follows (see Figure 6E-
2):
REMOVAL AND DISASSEMBLY. To remove and disassem-
1. Replace springs (04) and shoe linings (22).
ble the swing brake, proceed as follows (see Figure 6E-2):
2. If either bearing shows signs of wear or damage it should
1. Swing the upper so that shaft (34) is over the access
be replaced.
opening provided in the carrier deck. Place blocking at the
bottom of the shaft.
3. Inspect shaft (34) for defects. Replace the shaft if it is
worn, cracked or otherwise damaged.
2. Remove shield (07), spacers (08) and retainer (09).
4. Inspect sheave (10) for excessive wear and replace if
3. Remove the blocking and lower the shaft from the ma-
necessary.
chine.
5. If cylinder (44) leaks or has been performing erratically,
4. Disconnect lines (32) and remove pins (14). Remove the
overhaul it (see Subsection 5D).
brake mechanism from the machine and pull bearing (39)
from the shaft bore.
INSTALLATION. To install the swing brake, proceed as fol-
5. Remove bearing (37) from shaft (34).
lows (see Figure 6E-2):
