BASE AS 5396121 - Caterpillar

4. Separate pump halves (5) and (6). 5. Remove valve plate (7) and piston (9). 6. Remove four bolts (10) and plunger assembly (11). 7. Remove O-ring (12). 8. Remove gasket (13) and sleeve (14). 9. Remove two O-rings (15) and spring washer (16). 10. Remove piston rod (17) and locking pin (18). 11. Remove O-ring (19). 12. Remove bearing cup (20). 13. Remove gasket (21) and bearing (22). 14. Remove spacer (23).
During removal of the rotary group assembly (8) from the housing, do not let the assembly fall apart. Mark the piston assemblies so they can be reinstalled in their original bores in the slipper guide and cylinder block.
15. Lay housing (6) on side and remove rotary group (8). 16. Put identification marks on nine pistons (24) as to their location in the slipper guide (25) and cylinder block (26). Remove the piston assemblies (24) from the slipper guide (25) and the cylinder block (26). 17. Remove retainer guide (27), retainer (28) and three slipper hold down pins (29) from the cylinder block (26).
There is spring force against washer (30). When retaining ring (31) is removed, the spring force will be released. To prevent possible personal injury, removal of the internal components in cylinder block (26) should be performed in a press in order to retain spring (32) and washer (30).
18. Put cylinder block (26) in a press. Install a suitable drive plate of the same size as washer (30). Put a slight compression on washer (30) with the press. Remove the retaining ring (31) and slowly release the spring compression. 19. Remove notched washer (30), spring (32) and washer (33). 20. Remove four bolts (34). 21. Remove cover (35), O-ring (36) and shim pack (37). 22. Remove spacer (38), bearing cup (39) and bearing (40). Repeat above steps 20-22 for opposite side of pump housing (41). 23. Remove swash plate (42). 24. Remove spring seat (43) and spring (44). 25. Remove shaft (45) and bearing (46). Bearing (46) is a press fit on shaft (45). 26. Remove bearing cup (47). 27. Remove snap ring (48) and seal (49). The following steps are for the assembly of the auxiliary system pump. All pump components must be cleaned and inspected before assembly. If any components are worn beyond recommended limits they must be replaced. Lubricate all moving parts with clean oil during assembly. Assemble pump with all new seals. Install the seal (49) with the spring facing inward.28. Install seal (49) and snap ring (48). 29. Install bearing cup (47). 30. Install shaft (45) and bearing (46). 31. Install spring (44) and spring seat (43). 32. Install swash plate (42). 33. Install bearing (40), bearing cup (39) and spacer (38). 34. Install shim pack (37), O-ring (36) and cover (35). For proper bearing preload on swash plate (42), use equal shims (37) on both sides. The desired bearing preload is zero swash plate end play with very light effort needed to move swash plate from minimum to maximum