CONTROL GP-JOYSTICK 3751557 - Caterpillar

START BY:a. remove service brake or retarder master cylinder and rotochamber 1. Remove four bolts (1) and the lockwashers from head assembly (2) and the bracket. 2. Remove the head assembly, and remove seals (3). Inspect the seals, and make a replacement as needed. 3. Pull tube assembly (4), and remove it from the power piston. 4. Apply air pressure at the inlet air port to extend the rod and power piston (5) as shown.5. With the rod extended, remove power piston retainer ring (6) and power piston (5). Remove the flange and gasket. Inspect the gasket, and make a replacement if it is torn or damaged. 6. Remove seal ring and expander ring (7) and ring (8) from each end of the piston. Remove lip-type seal (9) from the piston. Inspect the seals and rings, and make a replacement as needed. 7. Remove two nuts (12) and lockwashers, and remove bracket (10) and the gasket. Make a replacement of the gasket if it is torn or damaged.8. Remove two locknuts (11) and the washers. 9. Install tooling (A) as shown.10. Carefully remove bolts (13) and the lockwashers.11. Use tooling (A) to slowly release tension on the brake spring. 12. Remove tooling (A). Remove cover (14) and brake spring (15). 13. Remove nuts (16) and the washers. 14. Pull the diaphragm unit out of body (17). 15. Remove nuts (18) and the washers. 16. Remove rod (19), guide (20), diaphragm (21), clamp (22) and clamp (23).Assemble Service Brake Or Retarder, Master Cylinder And Rotochamber
1. Put clamp (4) into position in clamp (5).2. Install guide (2) in diaphragm (3).3. Put the diaphragm and guide in position on the studs of clamp (4).4. Put rod (1) into position in guide (2), and install the washers and nuts on the studs.5. Put the outer lip of diaphragm (3) around the outer edge of clamp (5). Put 5P960 Multipurpose Type Grease on the diaphragm. 6. Install the diaphragm unit in body (6). 7. Install washers and nuts (7). Tighten the nuts to a torque of 24 7 N m (18 5 lb.ft.). 8. Put brake spring (9) and cover (8) into position on rod (10). 9. Install tooling (A). Use tooling (A) to put compression on spring (9) until cover (8) is in position in body (6). 10. Install the lockwashers and bolts (11). Tighten the bolts to a torque of 43 7 N m (32 5 lb.ft.). 11. Put bracket (12) into position on the rotochamber, and install the two lockwashers and nuts (13) to hold it in place. Make sure the gasket that goes between the bracket and the bottom cover of the rotochamber is not damaged. 12. Install washers (14) and locknuts (15) on the rod as shown. Tighten the locknuts to a torque of 100 14 N m (75 10 lb.ft.). The distance from the face of the rotochamber and the face of washer (14) must be 68.3 mm (2.69 in.).