SC-57 Felling Head Felling Head Caterpillar

Illustration 1	g00815846
345-9683 Piston Motor (A) Return port (B) Supply port

The pump rotation is counterclockwise.

Minimum displacement ... 79 cc/rev

Maximum displacement ... 160 cc/rev

Maximum operating pressure ... 31000 kPa (4500 psi)

Start of upstroke pressure ... 24130 ± 500 kPa (3500 ± 72 psi)

(1) Torque for the two locknuts ... 69 N·m (51 lb ft)

Illustration 2	g01642216
(5) Shuttle Valve

(2) 192-4671 Spring

Free Length ... 55 mm (2.2 inch)

Outside diameter ... 13.2 mm (0.52 inch)

(3) Torque for the check valve ... 200 N·m (148 lb ft)

(4) Torque for the eight bolts ... 215 N·m (160 lb ft)

(6) Torque for the bolt ... 150 N·m (111 lb ft)

(7) Stagger the seals in order to prevent leaks.

Illustration 3	g00816529
Shuttle valve

(8) Torque for the four bolts ... 130 N·m (96 lb ft)

Illustration 4	g00850502
Motor Rotating Group (9) Piston assembly

Piston rings are included in the piston assembly. Assemble with the mark on this side.

Apply 9S-3263 Thread Lock Compound to the threads prior to assembly.

(10) Torque for the 14 screws ... 15.5 ± 1.5 N·m (140 ± 13 lb in)

(11) 124-9861 Spring

Length ... 61 mm (2.4 inch)

Outside diameter ... 19.25 mm (0.758 inch)

Test load ... 1450 ± 136 N (326 ± 31 lb)

Test length ... 49.22 mm (1.938 inch)

(12) Available shims

124-9855 Shim ... 4.5 mm (0.177 inch)

124-9856 Shim ... 4.6 mm (0.181 inch)

124-9857 Shim ... 4.7 mm (0.185 inch)

124-9858 Shim ... 4.8 mm (0.189 inch)

124-9859 Shim ... 4.9 mm (0.193 inch)

124-9860 Shim ... 5.0 mm (0.197 inch)

In order to attain dimension (X), insert the shims, as required.

Measure dimension (X) after the rotating group is installed in the housing.

Dimension (X) ... 0.20 ± 0.10 mm (0.008 ± 0.004 inch)

Illustration 5	g00922029
Pilot Valve

(13) 123-5791 Spring

Free Length ... 19 mm (0.75 inch)

Outside diameter ... 10.3 mm (0.405 inch)

Piston Motor Mounting

Illustration 6	g02559118
345-9683 Piston Motor

(1) Torque of the eight bolts ... 360 ± 36 N·m (265 ± 27 lb ft)