Usage:
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 pinion and when no clutches are applied, spin freely on needle roller bearings. The bevel gears are splined to the friction 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 powerful, 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 manual. 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 bearing carrier, then remove the rotary seal assembly (17,26, 27).
Remove the six 1/2 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.
Using a wood block, bump the end of the clutch shaft at the left hand side of the winch to unseat the brake assembly. Remove the brake assembly. Retain the shim set for reassembly.
Grasp the brake hub and pull the clutch shaft assembly out of the winch through the brake opening.
Standard PTO Units
On 4-shaft standard PTO units, the clutch shaft pinion gear (28) will not clear the first reduction gear on the idler shaft. One of the following methods may be used to remove the clutch shaft assembly.
1. Refer to "Idler Shaft Service" and remove the first reduction gear and second reduction pinion assembly.
or
2. Remove the rotary seal shaft (24) and bearing retainer (22) from the left hand side of the clutch shaft. With a gear puller, remove the bearing cone (5) and pinion gear (28).
To facilitate removal of the clutch shaft assembly, have an assistant place a 3 ft. (1 m) length of 1 in. (25 mm) I.D. pipe over end of the rotary seal shaft and lift slightly as you both move the clutch shaft assembly out through the brake opening. Move the clutch shaft assembly out of the winch case far enough to place a lifting sling between the bevel gears.
Complete clutch shaft removal from winch case and place shaft assembly on clean work surface.
During disassembly, keep all components in the order in which they were removed.
Remove the rotary seal shafts (24) and bearing retainers (22) from each end of the clutch shaft.
With a gear puller, remove the pinion gear (28) and bearing cone (5) from the clutch shaft (if not already removed). Remove the brake hub (29) and bearing cone (9) from the clutch shaft.
Remove and discard o-rings (19) and back-up rings (23) from the clutch shaft.
Slide each clutch assembly off of the shaft. Refer to "Clutch Assembly Service" for additional information.
Remove the bevel gear thrust bearing assembly (7, 13, 25) from the shaft.
Remove the bevel gear and bearing carrier assemblies (3, 31) from the shaft. Inspect bearings (3) and press off gears if replacement is necessary. Note correct position of bearing (3) and carrier (31) retaining rings when installed on the bevel gears. The bearings have been "staked" into the carrier. If bearing replacement is necessary, use a press to remove and install the bearings. Use a center punch to "stake" the bearing carriers onto the bearings.
Remove the bevel gear needle bearings (8) and inner races (6) from the shaft.
Remove the bevel gear spacers (30) and shim set (33) from the shaft. Be sure to retain the shims for reassembly.
Assembly
Thoroughly clean and carefully inspect all components prior to assembly. If a components condition is questionable-replace it!
Due to machining tolerances, installation of any new components listed below will alter the original shim pack used between the bevel gears to establish the required backlash between the bevel gears and bevel pinion.
Measurements of components must be taken and used to establish a new shim pack thickness to maintain the required .004-.012 (.1-.31 mm) backlash)
Use the following formula and list of components to be measured to establish the new shim pack.
Due to machine tolerances, the thickness of the shim pack must be determined individually for each winch. The same parts which have been used for measuring must be used together.
Shim Pack Thickness:
Z = B1 + B2 + M1 + M2 - S1 - S2 - S3 - S4 - R1 - R2 - R3 - R4
The basic shim pack supplied through Service Parts is .120 in. (3.05 mm) thick.
Record dimensions M1 and M2, bevel gear mounting distance. The mounting distance has been etched into the inside surface of the bevel gears.
Measure and record dimension B1 and B2, thrust bearing assembly. Each thrust bearing assembly includes: one thrust bearing (7) and two thrust bearing races (13).
Measure and record dimension S1 and S2, thrust bearing, spacer thickness (25) and S3 and S4 bevel gear spacer thickness (30).
Measure and record dimension R1,R2, R3 and R4 bevel gear bearing inner race (6) thickness.
The shim pack thickness, (Z) to use in re-assembly of the clutch shaft is the total mounting distance of the bevel gears M1 and M2 plus the total thickness of the thrust bearing assemblies B1 and B2 less the total thickness of the bevel gear spacers S3 and S4, inner bearing races R1, R2, R3, R4 and thrust bearing spacers S1 and S2.
Begin the clutch shaft assembly by first installing the brake side components. Install the shim pack, Z (previously determined by the component measurement) onto the clutch shaft between the bevel gear spacer (30).
Install two inner bearing races (6) onto the brake side of the clutch shaft.
Install a bevel gear/bearing carrier assembly onto clutch shaft, positioning the bevel gear over the needle bearing races (6). Lubricate and install two needle bearings (8) between the bevel gear and the bearing races.
Lubricate and assemble the thrust bearing (7) between two thrust bearing races (13) and place over the splined thrust bearing spacer (25).
Install the thrust bearing assembly (7, 13, 25) onto the clutch shaft while fully seating the assembly against the bevel gear.
Lubricate and install an o-ring (19) and back-up ring (23) into the inner groove of the shaft with the back-up ring placed next to the splined thrust bearing spacer (25).
NOTE: The concave (cupped) side of the back-up ring (23) must always face the o-ring (19).
Install a clutch assembly onto the shaft aligning the splines of the clutch friction discs with the splines of the bevel gear. Seat the clutch over the o-ring and back-up ring installed on the clutch shaft.
Lubricate and install an o-ring (19) into the outer groove of the clutch shaft and seat into the clutch housing. Install the back-up ring (23) next to the o-ring. Install the brake hub spacer (36) onto the clutch shaft next to the clutch housing. The spacer should hold the o-ring and back-up ring into the clutch housing.
Install the brake hub (29) onto the clutch shaft with the small end against the spacer (36).
Install bearing cone (9) onto the clutch shaft. Press into position until the bearing cone seats securely against the shoulder of the shaft.
NOTE: Early rotary seal shafts require a 7/8 inch deep well socket, while current shafts require a 15/16 inch deep well socket for installation. New shafts are completely interchangeable with early ones.
Install rotary seal shaft (24) and retainer (22) onto the clutch shaft. Install the bearing retainer with the small diameter (chamfered) side toward the bearing cone. Apply Loc-tite 271 or equivalent to the threads and pilot shoulder of the shaft and tighten the early design to 40 lb-ft (54 N·m) torque. Tighten the current design to 130 lb-ft (175 N·m) torque.
Complete the assembly of the clutch shaft by installing the remaining components on the gear side of the shaft,
Lubricate and install two inner bearing races (6) onto the shaft.
Install the remaining bevel gear assembly over the inner bearing races.
Lubricate and install two needle bearings (8) between the bevel gear and bearing races.
Assemble the remaining thrust bearing, as described earlier, and install it onto the clutch shaft.
Lubricate and install an o-ring (19) and back-up ring (23) into the inner groove of the shaft, with the back-up ring placed next to splined thrust bearing spacer (25).
Install a clutch assembly onto the shaft, aligning the splines of the clutch friction discs with the splines of the bevel gear. Seat the clutch over the o-ring and back-up ring in the inner groove of the shaft.
Lubricate and install an o-ring (19) into the outer groove of the clutch shaft and seat into the clutch housing. Install the back-up ring (23) next to the o-ring.
Install spacer (32) over the clutch shaft, next to the clutch assembly. The spacer will hold the o-ring and back-up ring into the clutch housing.
Install the first reduction pinion gear (28) onto the clutch shaft next to the spacer.
Install bearing cone (5) onto the shaft. Press the bearing cone firmly against the pinion gear (28) until no clearance remains between any of the components of the clutch shaft.
Install the rotary seal shaft (24) and retainer (22) into the end of the clutch shaft. Install the bearing retainer with the large diameter (flat) side toward the bearing cone. Apply Loc-tite 271 or equivalent to the threads and pilot shoulder of the shaft and tighten to 40 lb-ft (54 N·m) torque. Tighten the current design to 130 lb-ft (175 N·m) torque.
Installation
Place the lifting sling between the bevel gears and install the clutch shaft assembly into winch case through the brake opening. Carefully slide the assembly into the center of the winch case where the bevel gear bearing carriers (31) are supported by the winch case.
The PA55 and PA56 winches are fitted with a rollpin (38) driven into outside surface of the bevel gear bearing carriers (31). These rollpins must be aligned with grooves machined in the inner case bores.
Lubricate and install three o-rings (16) into grooves of the winch case oil ports on the brake side.
Lubricate and install three (3) more o-rings (16) into grooves of the brake housing oil ports.
Use the shim set (34) removed during disassembly or a new shim set of the same thickness. Position shim set over the brake housing, aligning oil ports.
Lubricate and install o-ring (18) into the groove around the brake housing.
Install the brake housing and shim set into the winch case carefully aligning the oil ports. Make certain that all of the brake friction discs have engaged the brake hub (29) before installing capscrews.
Lubricate and install o-ring (16) into groove of winch case oil port and into groove of bearing carrier (35).
Use the original shim set or a new shim set of the same thickness. Position the shim set over the bearing carrier, aligning the oil port and bolt holes.
Lubricate and install the o-ring (18) around the bearing carrier cover.
Install rotary seal and o-ring (17, 27) into the bore of the cover. Install back-up washer (26) and secure with retaining ring (21).
Install the bearing carrier assembly (35) into the winch case, carefully aligning the oil port in the cover and shim set with the oil port in the winch case.
Move clutch shaft assembly from side to side by tapping rotary seal shaft with a wood block. End play should be .005 - .010 in. (.13-.25 mm).
Remove left hand bearing carrier cover and add or remove shims (34) as required to obtain correct end play.
Install plug (14) into bearing carrier cover.
Install bevel pinion and pump carrier assembly into the front of the winch. Use the original shim set and shim gasket, or new shim set and gasket of the same thickness.
Refer to :Bevel Pinion and Pump Carrier Service" for installation instructions and procedure for obtaining correct tooth contact pattern.
With correct bevel gear tooth contact pattern established, move clutch shaft assembly to the right (brake side). Gently tap wooden wedge between the bevel gear spacers and bevel pinion to move the bevel pinion away from the bevel gears, eliminating any axial bearing assembly clearance.
Place a dial indicator on the right hand bevel gear and check backlash reading of .004 - .012 in. (.10 - .31 mm).
Move the clutch shaft assembly to the left. Place a dial indicator on the left hand bevel gear and check backlash reading of .004 -.012 in. (.10 - .31 mm).
Transfer shims between brake housing and left hand bearing carrier to equalize the bevel gear backlash.
If an equalized bevel gear backlash reading is not obtainable, recheck bevel gear pinion tooth contact pattern and recheck end play in clutch shaft assembly.
Repeat backlash measurements on left hand and right hand bevel gears until and equalized .004 - .012 in. (.10 - .31 mm) reading is obtained.
Install plugs (14) into brake housing and left hand bearing carrier.
Make certain pump suction and pressure hoses and all capscrews are properly tightened.
Refill winch to proper level with recommended oil.