SUBSECTION 9C
PROPEL BRAKES
GENERAL
The information in this subsection covers the removal, re-
pair, and installation of the propel brakes used on this ma-
chine.
PROPEL BRAKES (15Z499)
DESCRIPTION
The propel brakes are of the spring set, hydraulically re-
leased disc type. One brake is bolted to each propel gear
case with the brake shaft splined into the gear case input
shaft. The propel motor output shaft is splined onto the
brake shaft.
The brake consists of a housing, piston, springs, friction
discs and disc separators. The friction discs are splined to
the brake shaft, and the disc separators are pinned to the
brake housing.
ADJUSTMENT
There are no propel brake adjustments. It is only required
that the hydraulic system be maintained properly, and that
the brake seals and discs are replaced when required. All air
must be bled from the brakes after servicing.
with a sling and proper lifting device. The brake and motor
OVERHAUL
weigh approximately 225 Ibs.
It should be kept in mind that the propel brakes are meant
DISASSEMBLY. To disassemble the propel brake, proceed
only as parking brakes and are not intended to stop the ma-
chine from traveling. This being the case, the friction discs
and disc separators will wear very Iittle. When the brakes
1. Place the brake on blocking with the shaft end down.
wear to the point that they do not hold the machine when
2. Alternately remove capscrews (23) to release plate (19).
parked, the discs must be replaced. Any time leakage at the
brake is noticed the brake must be removed from the ma-
3. Pull packing (05), and all discs, springs, and pins from
chine and the seals replaced.
housing (04).
NOTE
REMOVAL. To remove a propel brake, proceed as follows
Further disassembly of the housing is usually unnec-
essary, and should not be attempted unless a specific
1. Locate the machine on a firm level surface so the ma-
component must be replaced. If more complete dis-
chine wiII not move when the brake is removed. Engage the
assembly of the housing is necessary, complete steps
swing brake and block the crawlers.
4, 5 and 6.
2. Release all pressure in the brake circuit, and disconnect
the brake hydraulic line. Open the bleed screw to allow any
4. Pull seal (01) out of housing (04) taking care not to dam-
fluid to escape. Close the bleed screw.
age the seal in bearing (03).
5. Remove snap ring (02), then shaft (08) with bearing (03)
3. Mark the brake housing and the transmission case so
by lightly tapping the shaft with a plastic mallet.
the brake can be reinstalled in the same position. Remove
the capscrews which secure the brake and motor to the
6. Press the bearing off of the shaft by supporting the inner
gear case. Remove the brake and motor from the gear case
race of the bearing and applying pressure to the shaft.