330,330 L & 330 LN EXCAVATORS MACHINE SYSTEMS Caterpillar

1. Start the machine. Extend the stick completely, and lower the boom.

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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. Fasten a hoist to stick cylinder (3) as shown.

4. Disconnect two lube assemblies (4) at the head end of the stick cylinder. Put plugs in the ends of the tube assemblies to keep dirt and debris out of the hydraulic system. Disconnect the lubrication line for the mounting pin assembly at the head end of the stick cylinder.

5. Remove pin assembly retaining bolt (1) and the washer and pin assembly (2). Remove pin assembly retaining bolt (6) and the washer. Using tooling (A), remove pin assembly (5). Remove stick cylinder (3). The weight of the stick cylinder is 424 kg (935 lb).

NOTE: Some machines may be equipped with shims between the stick cylinder and boom at the stick cylinder-to-boom joint and at the stick cylinder and stick at the stick cylinder-to-stick pin joint. For assembly purposes, put identification marks on the shims as to their location.

6. Remove the shims (if so equipped) at the stick cylinder-to-boom pin joint and the stick cylinder-to-stick pin joint.

NOTE: The following steps are for installation of the stick cylinder.

7. Be sure the pin bores in the stick cylinder, boom and stick are clean and free of dirt prior to installation of the stick cylinder.

8. Fasten a hoist to stick cylinder (3), and put in position on the boom and stick. Be sure the pin bores in the stick cylinder are in alignment with the pin bores in the stick and boom.

9. Put a thin coat of 5P0960 Multipurpose Grease on pin assemblies (2) and (5). Temporarily install the two pin assemblies. Do not remove the hoist from the stick cylinder at this time.

Typical Example

10. Slide the stick cylinder to one side until it makes contact with the boom and the stick. Measure the total clearance between the stick cylinder and the boom and the stick cylinder and stick at each pin bore. The total clearance of (a) and (b) must not be more than 1.6 mm (0.06 in) at each pin bore. If the total clearance is less than 1.6 mm (0.06 in), the addition of shims between the stick cylinder and boom or the stick cylinder and stick will not be required. If the total clearance is more than 1.6 mm (0.06 in), add the correct thickness of shims to obtain the necessary clearance.

11. If it has been determined that shims need to be installed between the stick cylinder and boom and the stick cylinder and stick, remove pin assemblies (2) and (5). Install the shims between the cylinder and boom and the stick cylinder and stick; then, using tool (B), reinstall pin assemblies (2) and (5). Install pin assembly retaining bolts (1) and (6) that hold the pin assemblies in position. Tighten bolts (1) and (6) to a torque of 325 ± 40 N·m (240 ± 30 lb ft).

12. Check the condition of the O-ring seals in tube assemblies (4). If the seals are worn or damaged, use new parts for replacement. Connect tube assemblies (4) to the stick cylinder. Connect the lubrication line to the stick cylinder.

13. Fill the hydraulic oil tank with oil to the correct level. Lubricate the support pins for the stick cylinder. See the Operation & Maintenance Manual for the correct procedure.

Disassemble & Assemble Stick Cylinder

*If the Wolff Hydraulic Cylinder Repair Stand is not available to disassemble the stick cylinder, contact the Caterpillar Service Technology Group.

Start By:

a. remove stick cylinder

1. Put the bucket cylinder on tooling (A).

2. Remove bolts (9) that hold head (13) to cylinder assembly (1).

3. Use tooling (A) to slide rod assembly (10) out of cylinder assembly (1).

4. Remove ring (3), seal assembly (4) and ring (5) from piston (6).

5. Using tool (B), remove locknut (2) that holds piston (6) to rod assembly (10). Remove the piston from the rod assembly. Remove stop (7) from the rod assembly. Remove ring (8) from the stop.

6. Slide cylinder assembly (1) back onto the rod assembly. Install bolts (9) that hold head (13) to the cylinder assembly. Put the cylinder assembly and head (13) as a unit away from the rod assembly. Remove the head from the cylinder assembly.

7. Remove O-ring seal (14), ring (15), bearing (12), ring (11), seal (19), seal (18), ring (17) and lip-type seal (16) from head (13).

8. Remove the lip-type seal from both sides of the cylinder assembly and the rod assembly.

9. Remove the bearing from the cylinder assembly and the rod assembly.

NOTE: The following steps are for the assembly of the stick cylinder. Refer to illustration C49437P1 for assembly of the stick cylinder.

10. Install the bearing in the cylinder assembly and the rod assembly. Be sure the bearings are centered in the bore.

11. Using tool (C), install the lip-type seals in the rod assembly and the cylinder assembly. Install the seals with the lip facing out.

12. Install ring (11), bearing (12), seal (19), seal (18) and ring (17) in head (13) as shown. Using tool (C), install lip-type seal (16) in head (13) with the lip facing away from the inside of the cylinder. Install O-ring seal (14) and ring (15) in head (13) as shown.

13. Put clean hydraulic oil on the lip of the lip-type seal (16), ring (17), seal (18) and seal (19).

14. Put head (13) in position on cylinder assembly (1). Install bolts (9) that hold it. Install rod assembly (10) in head (13) and the cylinder assembly. Remove bolts (9). Remove cylinder assembly (1) from the rod assembly and head.

15. Install ring (8) on stop (7). The slit in the ring must turn in the direction of the piston as shown. Install stop (7) on rod assembly (10).

16. Install piston (6) on the rod assembly. Lubricate the threads on the end of the rod assembly with 2P2506 Threads Lubricant. Install locknut (2), and tighten it with tool (B) to a torque of 8000 ± 400 N·m (5920 ± 295 lb ft).

17. Install ring (3), seal assembly (4) and ring (5) on piston (6). Lubricate the outside of the piston with 1P0808 General Purpose Lubricant.

18. Using tooling (A), install cylinder assembly (1) on the rod assembly. Install bolts (9) that hold head (13) to the cylinder assembly. Tighten bolts (9) with the rod assembly fully extended.

End By:

a. install stick cylinder