330,330 L & 330 LN EXCAVATORS MACHINE SYSTEMS Caterpillar

Remove & Install Swing Motor

1. Prior to removing the swing motor, clean the swing motor and area around it.

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At operating temperature, the hydraulic oil tank is hot and under pressure. Hot oil can cause burns. To prevent possible personal injury, release the pressure in the implement hydraulic circuits (boom, stick and bucket) before any hydraulic lines or components are disconnected or removed.

2. Release the pressure in the hydraulic system as follows:

a. Fully retract the rod in the stick cylinder.

b. Adjust the position of the bucket so it will be flat on the ground when the boom is lowered.

c. Lower the boom until the bucket is flat on the ground.

d. Shut off the engine, and put the hydraulic activation control lever in the "Lock" position.

e. Move the control levers for the boom, bucket, stick and swing through their full travel strokes. This will relieve any pressure that may be present in the pilot system.

f. Slowly loosen the air breather cap on the hydraulic oil tank to release the pressure.

g. Tighten the air breather cap on the hydraulic oil tank.

h. The pressure in the hydraulic system has now been released. Lines and components can now be removed.

3. Remove the cover assembly located over the swing motor.

4. Put identification marks on all hose assemblies connected to the swing motor for installation purposes. Disconnect eight hose assemblies (1). Put plugs in the hose assemblies to keep dirt and debris out of the hydraulic system. Move the hose assemblies clear of the swing motor.

5. Remove four socket head bolts (3) that hold swing motor (2) to the swing drive.

6. Fasten a lifting strap and a hoist to the swing motor as shown. Remove the swing motor from the swing drive. The weight of the swing motor is 64 kg (140 lb).

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NOTICE
The O-ring seal used between the swing motor and swing drive may stay with either component during removal of the swing motor. Do not loose this O-ring seal.

7. Remove the O-ring from either the swing motor or swing drive.

NOTE: The following steps are for the installation of the swing motor.

8. Be sure the mating surfaces of the swing motor and swing drive are thoroughly clean and dry.

9. Check the condition of the O-ring seal used between the swing motor and swing drive. Also, check the condition of the O-ring seals used in the ends of hose assemblies (1). If any of the seals are worn or damaged, use new parts for replacement.

10. Install the O-ring seal on the swing motor. Put clean oil on the O-ring seal.

11. Fasten a lifting strap and a hoist to swing motor (2), and put it in its original position in the swing drive. Install four socket head bolts (3) that hold it.

12. Reconnect hose assemblies (1) in their original locations.

13. Fill the hydraulic oil tank and swing drive with oil to the correct level. See the Operation & Maintenance Manual for the correct filling procedure.

14. Start the machine, and check the operation of the swing drive. Also, check for leaks.

15. Reinstall the cover assembly over the swing motor.

Disassemble Swing Motor

Start By:

a. remove swing cover

NOTE: The disassembly and assembly procedure which follows is for a swing motor which has a swing parking brake attachment. If the swing motor is equipped with a swing parking brake, it will also have a brake valve group which is mounted to the body of the swing motor.

1. Be sure the outside of the swing motor is clean and free of dirt and debris prior to disassembly.

Typical Example

2. Put the swing on wood blocks as shown. Put identification marks on each relief valve assembly (1) as to its location in the swing motor. Remove two relief valve assemblies (1).

3. Remove the brake valve group from the body of the swing motor. The brake valve group is located under relief valve assemblies (1).

4. Remove the cushion crossover relief valve group from the head of the swing motor.

5. Remove O-ring seal (3) and back-up ring (2) from each relief valve assembly.

NOTE: For the disassembly procedure for relief valve assemblies (1), see Steps 25a through 25m. For the disassembly procedure for the brake valve group, see Steps 26a through 26e. For the disassembly of the cushion crossover relief valve group, see Steps 27a through 27d.

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NOTICE
Put identification marks on the components of each make-up valve (4) as they are removed from the valve casing of the swing motor. The components of each make-up valve must be reinstalled in their original locations.

6. Remove two make-up valves (4) from the head of the swing motor. Remove plugs (7), springs (6) and valves (5). Remove O-ring seal (8) from each plug (7).

7. Put an alignment mark on head (10) so it can be reinstalled in its original position on the swing motor body.

8. Remove four socket head bolts (9) and head (10) from the swing motor body.

9. Remove O-ring seal (11) and bearing (12) from the head. If necessary, remove two pins (13) from the valve casing.

10. Remove twenty springs (14) from the piston.

11. Remove plate (15) from the barrel assembly.

NOTE: When tooling (A) is installed to remove piston (16), install the threaded rods into holes (X) as shown.

12. Mark the position of piston (16) in the swing motor body for assembly purposes. Install tool (A) in piston (16) as shown. Remove piston (16) from the swing motor body with tooling (A).

13. Remove three separator plates and two friction plates (17) from the piston.

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NOTICE
During removal of barrel assembly (18) from swing motor body, do not let the components come apart. All parts in the barrel assembly must be reinstalled in their original locations.

14. Put the swing motor on its side as shown. Remove barrel assembly (18) from the shaft in body (19).

15. Disassemble barrel assembly (18) as follows:

a. Put identification marks on nine piston assemblies (20) as to their location in plate (21) and barrel (22). Remove nine piston assemblies (20) and plate (21), as a unit, from barrel (22). Separate the piston assemblies from the plate.

b. Remove bushing (23) from the barrel. Remove the spacer from the bushing.

NOTE: There are twelve pins (24) in barrel (22). Two pins are used in each hole location.

c. Remove twelve pins (24) from the barrel.

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There is spring force against spacer (26). When retaining ring (25) is removed, the spring force will be released. To prevent possible personal injury, removal of the internal components in barrel (22) should be performed in a press in order to retain spring (27) and spacer (26).

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NOTICE
Spacer (26) and spacer (28) are different in size. Put identification marks on the two spacers as they are removed so they can be reinstalled in their original locations.

d. Put barrel (22) in a press. Install a suitable size drive plate that is slightly smaller in diameter then spacer (26), on spacer (26). Put a slight amount of compression on spacer (26) with the press. Remove retaining ring (25), and slowly release the spring compression. Remove spacer (26), spring (27) and spacer (28) from barrel (22).

16. Remove O-ring seals (29) and (30) from the body.

17. Remove retaining ring (31) that holds shaft assembly (32) in the body.

18. Use a soft faced hammer to remove shaft assembly (32) and retainer (33) from the body. Remove the shaft assembly in the direction shown.

19. Remove plate (34) from the body. It may be necessary to use a hammer and punch to remove the plate.

20. Remove ring (35) and retainer (33) from the shaft.

21. Remove oil seal (36) from front cover (33).

22. Remove retaining ring (37) and bearing race (39) from the end of the shaft.

23. Remove two retaining rings (40) and the spacers (one on each side of the bearing) that position bearing (28) on the shaft.

24. Put the shaft in a press. Press the shaft out of bearing (38).

25. Disassemble relief valves (1) as follows:

a. Remove plug (41).

b. Remove O-ring seal (42) and back-up ring (43) from the plug.

c. Remove spring (44).

d. Remove seat (45).

e. Remove locknut (46).

f. Remove body (47).

g. Remove retainer (48).

h. Remove ball (49) from the larger of the two holes in the body.

i. Remove insert (50) and insert (51) from body (47).

j. Remove back-up ring (52) and O-ring seal (53) from body (47).

k. Remove spring (54) from body (55).

l. Remove retainer (56) from the body.

m. Remove valve (57) from the body.

26. Disassemble the brake valve group as follows:

a. Remove O-ring seals (64) and O-ring seal (67) from the valve body.

b. Remove spring (65) and spool (60) from the valve body.

c. Remove spring (66) and spool assembly (61) from the valve body.

d. Remove ball (62) from valve body.

e. Remove plug (63) from the valve body.

27. Disassemble the cushion crossover relief valve group as follows:

a. Remove spring (68) from valve body (71).

b. Remove ring (74), O-ring seal (75) and ring (76) from valve body (71).

c. Remove plug (73) from valve body (71). Remove O-ring seal (72) from the plug.

d. Remove shims (77), the spool assembly and springs (69) and (70) from valve body (71).

Assemble Swing Motor

1. Be sure all parts of the swing motor are clean and free of dirt and debris prior to assembly. Check the condition of all parts in the swing motor. Guideline For Reusable Parts "Piston Pumps And Motors", Form No. SEBF8032-01 can be used as a guide for reconditioning and determining the reusability of some parts.

2. Check the condition of all O-ring seals and back-up rings used in the swing motor and the relief valves. If any of the seals are worn or damaged, use new parts for replacement.

3. Assemble the cushion crossover relief valve as follows:

a. Install springs (70) and (69), the spool assembly and shims (77) in valve body (71).

b. Install O-ring seal (72) on plug (73). Install plug (73) in valve body (71). Tighten the plug to a torque of 148 ± 10 N·m (105 ± 7 lb ft).

c. Install spring (68) in valve body (71).

4. Assemble the brake valve group as follows:

a. Install plug (63) in the valve body.

b. Install ball (62) in the valve body.

c. Install spool assembly (61) and spring (66) in the valve body.

d. Install spool (60) and spring (65) in the valve body.

e. Install O-ring seals (67) and (64) in the valve body.

5. Assemble relief valves (1) as follows:

a. Install valve (57) in the body as shown.

b. Install retainer (56) on the body as shown.

c. Install spring (54) in body (55).

d. Install back-up ring (52) and O-ring seal (53) on body (47). Be sure the seal and ring are in the positions shown.

e. Install insert (51) and insert (50) in body (47) as shown.

f. Install ball (49) in the larger of the two holes in body (47).

g. Install retainer (48) on the body assembly as shown.

h. Install body (47).

i. Install locknut (46) in body (47). Locknut (46) must be tightened to a torque of 160 ± 30 N·m (120 ± 22 lb ft) after adjustment of the valve is made.

j. Install seat (45) as shown.

k. Install spring (44).

l. Install O-ring seal (42) and back-up ring (43) on plug (41) as shown.

m. Install plug (41) in relief valve (1). Plug (41) must be tightened to a torque of 120 ± 10 N·m (90 ± 7 lb ft).

NOTE: To adjust the pressure settings of each relief valve (1), see the Hydraulic Systems Testing And Adjusting module.

6. Install one of the retaining rings (40) on the drive shaft.

7. Press the drive shaft into bearing (38) until it makes contact with the retaining ring. Install the other retaining ring (40) on the other side of the bearing.

8. Install bearing race (39) and retaining ring (37) on the end of the drive shaft.

9. Install oil seal (36) in front cover (33) with tool (A). Install the seal so the lip will be facing away from the outside of the front cover, and until it makes contact with the counterbore in the front cover.

10. Install shaft assembly (32) in the body. Be sure bearing (38) is seated in the counterbore in the body.

11. Lubricate the lip of oil seal (36) with clean hydraulic oil. Install front cover (33) over shaft assembly (32) and into the body with a soft faced hammer.

12. Install retaining ring (31) that holds the shaft assembly in place. Install ring (35) on shaft assembly (32).

13. Put a thin coat of 5P0960 Multipurpose Grease on the back side of plate (34). Install plate (34) in the body.

14. Install O-ring seals (29) and (30) in the body as shown.

15. Assemble barrel assembly (18) as follows:

a. Install spacer (28), spring (27) and spacer (26) in barrel (22). Put the barrel in a press. Install a suitable size drive plate on spacer (26), a compress spring (27) until retaining ring (25) can be installed. Install retaining ring (25).

b. Install twelve pins (24) in barrel (22).

c. Install the spacer in bushing (23). Install bushing (23) on pins (24).

d. Put clean hydraulic oil on nine piston assemblies (20). Install the piston assemblies in their original bores in plate (21). Install the plate with the piston assemblies in their original bores in barrel (22).

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NOTICE
Do not let the barrel assembly fall apart when it is installed in the body.

16. Put body (19) on its side. Install barrel assembly (18) in the body.

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NOTICE
The four tooth cut locations of each friction plate must be in alignment. Also, the four tooth cut locations of each separator plate must be in alignment in the body.

17. Put clean hydraulic oil on three separator plates and two friction plates (17). Install the plates in alternating order in the body. Start with a separator plate, and end with a separator plate.

18. Instal piston (16) in the body in its original position. Threaded holes (X) can be used as a guide during installation. If the piston is hard to install because of O-ring seal resistance, a soft faced hammer can be used as an aid in installation.

19. Install twenty springs (14) in the piston.

20. Install two pins (13) and bearing (12) in head (10).

21. Install O-ring seal (11) on head (10).

22. Put a thin coat of 5P0960 Multipurpose Grease on the face of plate (15) that makes contact with the head. The grease will hold the plate to the head. Install the plate on the head in its original position as shown in the illustration.

23. Put head (10) in its original position on the body. Install four socket head bolts (9) that hold it. Tighten the socket head bolts to a torque of 430 ± 43 N·m (320 ± 32 lb ft).

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NOTICE
Be sure to install each make-up valve (4) in its original position in the head.

24. Install two make-up valves (4) in the head. Install O-ring seals (8) on plugs (7). Install valves (5), springs (6) and plugs (7). Tighten plugs (7) to a torque of 220 ± 20 N·m (160 ± 15 lb ft).

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NOTICE
Be sure to install each relief valve assembly (1) in its original position in the head.

25. Install back-up ring (2) and O-ring seal (3) on each relief valve assembly (1) as shown in Photo C48291P1.

26. Install relief valve assemblies (1) in the head. Tighten the relief valve assemblies to a torque of 180 ± 10 N·m (135 ± 7 lb ft).

27. Reinstall the cushion crossover relief valve in the head of the swing motor.

28. Reinstall the brake valve group on the swing motor.

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NOTICE
To prevent damage to the swing motor, the unit must be filled with hydraulic oil at least to the fill port prior to operation. See the Operation & Maintenance Manual for the correct filling procedure.

End By:

a. install swing motor