PR-75 2000 SERIES MOTOR 2000 Series Motor Caterpillar

2000 Series Motor
PR-75 2000 SERIES MOTOR [KEBR2350]
PR-75 2000 SERIES MOTOR 2000 Series Motor

Torque wrench 500 lb-in [57 Nm] capacity12-16 [300-450]* breaker bar9/16 socketSmall screwdriver 6-8×1/4[150-200×6,5] blade3/16 allen wrenchPress

*Unless indicated otherwise, measurements are given in inches[mm]. **Shaft seal installation tool (600496)**Bullet (600465) for 1 diameter shafts

The following tools are not necessary for disassembly and reassembly, but are extremely helpful.

Alignment studs (2) (for standard and wheel motors only)

**Available--by special order

Cleanliness is extremely important when repairing a hydraulic motor. Work in a clean area. Before disconnecting the lines, clean the port area of the motor thoroughly. Use a wire brush to remove foreign material and debris from around the exterior joints of the motor. Check the shaft and keyslot, remove all nicks, burrs or sharp edges that might damage the bearing housing seals when installing the shaft and bearing assembly. Before starting the disassembly procedures, drain the oil from inside the motor.

Figure 1

1 Place the motor in a vise with the output shaft down. Clamp across the mounting flange of the motor not the housing. Excessive clamping pressure will cause distortion. When clamping, use some protective device on the vise, such as special soft jaws, pieces of hard rubber or board.

NOTE: Although not all drawings show the motor in a vise, we recommend that you keep the motor in the vise during disassembly and reassembly. Follow the clamping procedures explained throughout the manual.

Figure 2

2 Remove 4 bolts from motor.

Figure 3

3 Lift valve housing straight up. If done carefully the pins, springs, balance ring assembly, and valve will remain on the valve plate.

Figure 4

4 Carefully remove 76mm (3") diameter seal from valve housing.

5 Remove case drain plug-with seal, from valve housing.

6 Remove 2 pins and 2 springs from balance ring assembly, see Fig. 5.

Figure 5

7 Remove balance ring assembly.

8 Remove inner and outer face seals from balance ring.

9 Remove the valve.

Figure 6

10 Remove the valve plate.

11 Remove the 76mm (3") diameter seal from valve plate.

12 Remove the valve drive.

Figure 7

13 Remove the Geroler. Be sure to retain the rollers in the outer ring if they are loose.

14 Remove the drive.

15 Remove the 76mm (3") diameter seal from wear plate, see Fig. 7.

Figure 8

16 Remove the wear plate.

17 Remove the shaft face seal from the wear plate.

18 Remove the 76mm (3") diameter seal from bearing housing.

Figure 9

19 You may need a press to remove shaft and bearing assembly from bearing housing.

Figure 10

20 Use a small screwdriver to remove shaft seal, back-up washer and dust seal from bearing housing, see Fig. 10. Do not damage bore of housing.

NOTE: Individual parts of shaft and bearing assembly are not sold separately. Replace as a unit.

Check all mating surfaces. Replace any parts that have scratches or burrs that could cause leakage. Clean all metal parts in clean solvent. Blow dry with air. Do not wipe dry with cloth or paper towel because lint or other matter can get in the hydraulic system and cause damage. Do not use a coarse grit or try to file or grind these parts. Check around the keyway and chamfered area of the shaft for burrs, nicks or sharp edges that can damage the seals when reassembling the bearing housing.

NOTE: Lubricate all seals (prior to installation) with petroleum jelly such as Vaseline. Use new seals when reassembling this motor. Refer to parts list (6-129) for proper seal kit number.

21 Use a press to install dust seal in outer bore of bearing housing. Lip of seal must face outward. See Fig. 11. If a press is not available use a plastic or rubber hammer, being careful not to damage or cock seal in the bore.

22 Place back-up washer into seal bore. Place shaft seal onto installation tool (600496) and press seal into seal bore of the housing.

23 Clamp housing in vise, see Fig. 1.

24 Place protective bullet (see note below) over shaft. Apply petroleum jelly to inside diameter of dust and shaft seal. You may need a press to install shaft and bearing assembly. Do not distort shaft seal. Damage to this seal will cause leakage.

NOTE: Bullet (600465), for 1" shafts, available-by special order. Use tape over other shafts to prevent cutting the seals.

25 Apply petroleum jelly to the 76mm (3") diameter seal. Install seal into the bearing housing.

26 Alignment studs can be very helpful in reassembly of the motor. See special tool listing page 2. If you use studs, install 2 studs diagonally opposed in the bearing housing.

27 Install the shaft face seal in the wear plate as shown in Fig. 11. Do not distort seal.

28 Install the wear plate, see Fig. 11.

29 Apply a light film of petroleum jelly to the 3[76] diameter seal and install seal in the wear plate.

30 Install the drive in the bearing housing.

31 Align the notch on the outside of the Geroler with the notch on the wear plate. Install the Geroler against the wear plate. Be sure to retain the rollers in the outer ring if they are loose.

NOTE: Installation at this time involves 3 steps in the timing of the motor. Timing determines the direction of rotation of the output shaft. Timing parts include:

1. Geroler
2. Valve Drive
3. Valve Plate
4. Valve

Figure 12 Timing Alignment

Timing Step # 1-Locate the largest open pocket in the Geroler and mark it on the outside edge of the Geroler.

32 Install the valve drive in the Geroler.

33 Apply a light film of petroleum jelly to the 76mm (3") diameter seal. Install seal in groove of valve plate.

34 Align the notch on the outside of the valve plate with the notch on the Geroler as shown in Fig. 12.

Timing Step # 2- Locate the slot opening in the valve plate which is in line with the largest open pocket of the Geroler.

Timing Step # 3- Locate any one of the side openings of the valve and align this opening with the open slot of the valve plate that is in line with the largest open pocket of the Geroler. Install the valve by rotating it clockwise until the spline teeth engage (1/2 spline tooth). This will provide the proper rotation when pressurized as shown in Fig. 13.

Figure 13

Figure 14

35 Install 2 springs and 2 pins in the holes located in the bore of the valve housing, as shown in Fig. 14.

36 Apply a light film of petroleum jelly to the 76mm (3") diameter seal. Install seal in the valve housing.

37 Apply petroleum jelly to inner and outer face seals. Install seals on balance ring as shown in Fig. 15.

Important: Install face seals in the positions shown in Fig. 15. or the motor will not operate properly. Do not force or bend the face seals. Any damage to these seals will affect the operation of the motor.

Figure 15

38 Align pin grooves in balance ring with pins in bore of valve housing. Install balance ring assembly in valve housing.

Figure 16

Figure 17

39 Insert your finger through port of housing. Apply pressure to side of balance ring as shown in Fig. 16. Hold ring in position until valve housing is in place. Install valve against valve plate as shown in Fig. 17.

NOTE: After installing the valve housing on the valve plate check for proper placement. Push down on the valve housing. You should get a slight spring action.

Figure 18

40 Install the tie bolts. If you use alignment studs, install 2 bolts opposite the studs. Finger tighten the bolts. Remove the alignment studs and replace with the 2 remaining bolts. Torque all 4 bolts alternately to 450 lb-in[50Nm].

41 Install seal on case drain plug then install in valve housing. Torque to 50 lb-in[6Nm].