MAINTENANCE 4.12 EVERY 1000 OPERATING HOURS OR EVERY 6 MONTH High-Strength Bolt Connections (continued) G Check fastening and condition of main hydraulic pumps (1-6), illust. Z 20710. Mounting bolt size: M20, Grade 8.8, tightening torque 360 Nm. G Check fastening and condition of auxiliary pumps (8.1 - 8.6) and secondary hydraulic pumps (10.1 - 10.4). Mounting bolt size: M12, Grade 8.8, tightening torque 74 Nm. Pump Description: (1-6) Main hydraulic pumps, swash plate type for all work- ing and travelling motions. (8.1- 8.6) Gear type pumps. (10.1- 10.4) Axial piston pumps. 393