Paccar CARCO 50B, Service Manual

Page: 35 / 61

33
CLUTCH SHAFT SERVICE
DESCRIPTION
The clutch shaft assembly contains or supports the two
bevel gears, the Reel-In and Reel-Out clutches, the brake
hub and the first reduction pinion gear.
OPERATION
The bevel gears are continuously driven by the bevel pin-
ion and, when no clutches are applied, spin freely on nee-
dle roller bearings. The bevel gears are splined to the fric-
tion discs of the clutches. The steel clutch discs are
splined to the clutch housing and the clutch housing is
splined to the clutch shaft.
When a clutch is applied, the clutch piston compresses
the friction and steel discs tight enough to transmit power
from the bevel gears to the clutch shaft. The direction the
clutch shaft turns depends on which clutch is applied.
The clutch shaft transmits power to the winch reduction
gears through the small pinion gear splined to the left
hand end of the shaft.
Splined to the right hand end of the clutch shaft is the
brake hub which is splined to the friction discs of a pow-
erful, load holding multi-disc oil brake. The friction discs
are alternately stacked between steel discs which are
splined to the brake housing which is anchored to the
winch case.
The brake is spring applied and hydraulically released.
The clutch shaft and the entire winch gear train is held
firm by the brake until hydraulic oil pressure overcomes
the spring force to relieve the compression of the discs.
When released, the clutch shaft and brake hub can turn
as the brake friction discs slip freely between the brake
steel discs.
The bevel gears and center portion of the clutch shaft are
supported by two large ball bearings while the ends of the
shaft are supported by two tapered roller bearings.
The clutches are supplied with application oil pressure
from passages drilled through the center of the shaft.
Clutch application oil travels from the control valve to the
clutch shaft bearing carriers where the oil passes through
a rotary seal shaft installed in the drilled passages at the
ends of the shaft.
REMOVAL
Drain oil and remove winch from tractor as described in
the “Winch Removal and Installation” section of this man-
ual. Remove only the winch, leaving the mounting blocks
attached to the tractor; where applicable.
Remove the six capscrews then remove the bevel pinion
and pump carrier from the front of the winch. Retain the
shim set for reassembly. Refer to “Bevel Pinion and Pump
Carrier Service” for additional information.
Remove the six capscrews (10) then remove the left hand
clutch shaft bearing carrier (35). Retain the shim set for
reassembly. Inspect the bearing cup (4) in the bearing
carrier and replace as required.
Remove the retaining ring (21) from the bore of the bear-
ing carrier, then remove the rotary seal assembly (17, 26,
27).
Remove the six ½ in. capscrews securing the brake
assembly to the winch case. DO NOT remove the two 3/8
in. capscrews securing the outer bearing carrier cover to
the brake housing at this time. Refer to “Brake Assembly
Service” for additional information.
ITEM DESCRIPTION QTY.
17 O-Ring 2
21 Retaining Ring 2
22 Bearing Retainer 2
24 Rotary Seal Shaft 2
26 Back-Up Washer 2
27 Rotary Seal 2
40 Orifice Plug 2