TILT CYLINDER AND SEAL GROUP 7K9412 - Caterpillar

With the boom positioned on tooling (A), the end of the boom should be approximately six feet above the ground and the hook on the lower sheave block should be just off the ground.1. Wind the lower sheave block in until it is approximately one foot from the bottom of the upper sheave block. Position tooling (A) under the boom frame bracing located below the rod end of the boom cylinder and lower the boom on to tooling (A). 2. Fasten a hoist to boom cylinder (1) as shown. 3. Remove three bolts (3) and the washers, and remove bar (4). Remove pin (2) from the rod end of boom cylinder (1).4. Retract the boom cylinder to protect the cylinder rod during the removal of the boom cylinder. 5. Remove two bolts (6) and remove guard (7).
At operating temperature, the hydraulic oil tank is hot and under pressure. Hot oil can cause burns. Remove the filler cap only when the engine is stopped and the filler cap is cool enough to touch with your bare hand.
6. Release the pressure in the hydraulic system by slowly loosening the filler cap located on the top of the hydraulic oil tank.7. Release the pressure in the boom cylinder by slowly turning tube assembly (5) counterclockwise as shown.
Do not disconnect oil lines (8) until the pressure in the boom cylinder has been released.
8. Disconnect oil lines (8) from the boom cylinder. Cap or plug all openings as each hose is disconnected. 9. Raise the boom cylinder to a horizontal position. Remove bolt (9) and the washer, and remove pin (10). Remove the boom cylinder. Weight of the boom cylinder is 907 kg (2000 lb). The following steps are for the installation of the boom cylinder.10. Clean the pins and the pin bores. Put 5P0960 Molybdenum Grease on the pin bores.11. Fasten a hoist to the boom cylinder. Put the boom cylinder in position and install pin (10). Install bolt (9) and the washer to secure the pin.12. Connect oil lines (8).13. To tighten, turn tube assembly (5) clockwise. Tighten the tube assembly to a torque of 20 3 N m (15 2 lb ft).14. Put guard (7) in position and install two bolts (6).15. Lower the boom cylinder until it is in a straight line with the pin bore in the boom. Extend the rod until the bore in the rod is in alignment with the bore in the boom and install pin (2). Install bar (4), three bolts (3), and the washers to secure the pin.16. Raise the boom and remove tooling (A).