UPPERSTRUCTURE / Control Valve Assemble Control Valve (5-Spool Housing Upper and Lower Surfaces) Assemble Overload Relief Valve-1 1. Install O-ring (52), backup rings (24) (2 used) and O-ring (23) to seat (53). Install O-ring (48) to adjusting screw (47). IMPORTANT: Align the matching marks and tighten adjusting screw (47) to the same turns when disassembling. 2. Install pilot poppet (50), spring (49), adjusting screw (47) and lock nut (46) to seat (53). 3. Install O-ring (28), backup ring (29) and O-ring (30) to sleeve (57). 4. Install piston (55) to main poppet (56). Install main poppet (56) to sleeve (57). 5. Install springs (54, 51) to the seat (53) assembly.
Install the seat (53) assembly to sleeve (57). Assemble Check Valve-1, Check Valve-2 7. Install O-rings (32, 37) and backup ring (33) to cap (check valve-1: 31, check valve-2: 36). Install spring (34), check valve (35) and cap (check valve-1: 31, check valve-2: 36) to housing (64). : 14 mm : 350 N m (36 kgf m, 258 lbf ft) Assemble Check Valve-3 8. Install O-ring (39) to cap (38). Install O-ring (41) to spacer (40). Install check valve (43), spring (42), spacer (40) and cap (38) to housing (64). : 8 mm : 50 N m (5.1 kgf m, 37 lbf ft) : 100 N m (10 kgf m, 74 lbf ft) IMPORTANT: Install overload relief valve-1 to the original position before disassembling.
Adjust pressure of the overload relief valve by using a test bench. (Refer to the Operational Performance Test section / TROUBLESHOOTING in the separated volume, T/M.) : 36 mm 6. Install overload relief valves-1 (4 used) to housing (64). : 41 mm : 100 N m (10 kgf m, 74 lbf ft) NOTE: Tighten the hexagonal part of sleeve (57). W2-5-49