HYDRAULICS 1.118 2. Drain as much hydraulic fluid as possible from the cylinder into a suitable container before dismantling. 3. Support cylinder on ‘V’ blocks; make sure that when the piston is removed the components are not damaged. If compressed air is used to extend the piston assembly, the threaded cap (1) must not be removed. Release all pressure before the threaded cap is removed. 4. When the piston assembly is difficult to extend, a compressed air supply may be used to pressurize the cylinder. Use only the minimum pressure necessary to extend piston. 5. Using a suitable spanner, unscrew the threaded cap (1) from the cylinder (2). 6.
Withdraw the piston rod (3) complete with piston assembly (4) and gland assembly (10) from the cylinder (2). If necessary carefully tap the fork-end of the piston rod with a soft faced hammer to remove piston rod. 7. Remove the grub screw (5) from the inner piston half (6) unscrew and remove the inner piston half from the piston rod. 1. Threaded cap 2. Cylinder 3. Piston rod 4. Piston assembly 5. Grub screw 6. Inner piston half 7. Seal 8. O-ring 9. Outer piston half 10. Gland assembly 11. O-ring 12. Seal 13. Wiper ring 14. Gland nut 8. Remove and discard the seal (7) O-ring (8) and outer piston half (9) from the piston rod. 9.
Remove the gland assembly (10) and threaded cap (1) from the piston rod. Remove and discard the O-ring (11), seal (12) and wiper ring (13) from the gland nut (14). Assembly 1. Assemble the autohitch cylinder in the reverse order to dismantling. 2. Use new O-rings, seals and spacers during assembly. 3. Make sure all old Loctite is removed from the threads of the inner piston half, piston rod and grub screw before assembly. Apply Loctite sealant to threads of piston rod and grub screw and securely screw inner piston half to piston rod before fitting grub screw. 4. Lubricate O-rings, seals and wiper ring with clean