Paccar CARCO 50B, Руководство по обслуживанию, Страница: 47 / 61

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Install three O-Rings (4) into the oil port grooves on the
outer end of the brake housing.
Lubricate and install the rotary seal with o-ring into the
bore of the bearing carrier cover, with the flat side of the
rotary seal facing toward the back-up washer and retain-
ing ring. Secure in place with the retaining ring.
If the bearing cup was removed, install a new bearing cup
(1) into the bearing carrier cover.
Install O-Ring (7) into the groove on the pilot of the bear-
ing carrier.
Install the bearing carrier (18) onto the brake housing
while aligning the oil ports between the two housings.
Install the two 3/8 in. capscrews (2) and tighten to 31 lb•ft
(42 N•m) torque.
BRAKE ASSEMBLY TEST PROCEDURE
The following test procedure may be used to check the
condition of the brake piston seals and the actual pres-
sure required to fully release the brake.
Lubricate and install an O-Ring (4) into the grooved brake
housing port labeled with a “B” cast onto the bearing car-
rier.
Clamp a piece of steel bar over the port now sealed by
the o-ring.
Locate the external brake release port next to the “B” cast
into the bearing carrier. The port is -6 ORB on current
units. Attach a hand pump with an accurate 0-500 psi (0-
3450 kPa) gauge teed into the line.
With the hand pump, slowly increase pressure applied to
the brake and record what pressure is required to fully
release the brake and permit free movement of the brake
discs with a screwdriver.
The brake should be fully released at approximately 230
- 250 psi (1590 - 1720 kPa).
Continue to increase pressure to 350 psi (2410 kPa).
Close the hand pump valve and let stand for five minutes.
If there is any loss of pressure in five minutes, the brake
cylinder should be disassembled for inspection of the
seals and sealing surfaces.
While pressure is applied and the brake is released, align
the friction discs. If the clutch shaft group has been dis-
assembled, use the brake hub to align the splines of the
discs.
INSTALLATION
Refer to “Clutch Shaft Service” for additional information.
Install three o-rings in the grooves on the brake housing
and three o-rings in the grooves on the winch case.
Install the original shim set between the brake housing
and winch case. If the shim set must be replaced, refer to
the “Clutch Shaft Service” section for additional informa-
tion.
Lubricate and install the o-ring into the groove on the
outer diameter of the brake housing.
Install the brake assembly into the winch case, aligning all
ports of winch case, shim set and brake assembly.
Install the six capscrews which secure the brake housing
to the winch case. Tighten to 75 lb•ft (102 N•m) torque.
Refill winch to proper level with recommended oil.
One brake spring must “nest” within the shallow cavity
on the outside of the brake piston while the other brake
spring will “nest” in the shallow cavity in the bearing car-
rier. If the springs slip out of the cavities during assem-
bly, brake component damage and improper brake oper-
ation may occur. Improper brake operation may lead to
loss of load control which may result in property dam-
age, injury or death.