784B and 785B Off-Highway Truck/Tractor Air System and Brakes Caterpillar

Illustration 1	g00289601

(1) Torque for two bolts ... 105 ± 20 N·m (77 ± 15 lb ft)

(2) 3G-6849 Relief Valve Group

Test the relief valve group on the machine.

Pressure setting ... 17300 ± 200 kPa (2510.0 ± 29.0 psi)

Flow rate ... 334 ± 8 L/min (88.0 ± 2.0 US gpm)

(3) 5J-4664 Spring for dump valve

Length under test force ... 28.9 mm (1.14 inch)

Test force ... 39 ± 4 N (9 ± 1 lb)

Free length after test ... 36.3 mm (1.43 inch)

Outside diameter ... 12.7 mm (0.50 inch)

(4) 4J-7066 Spring for check valve

Length under test force ... 51.6 mm (2.03 inch)

Test force ... 17 ± 1 N (3.8 ± 0.2 lb)

Free length after test ... 76.2 mm (3.00 inch)

Outside diameter ... 28.4 mm (1.12 inch)

(5) 9J-5006 Spring on valve spool

Length under test force ... 42.2 mm (1.66 inch)

Test force ... 193 ± 9 N (43.4 ± 2.0 lb)

Free length after test ... 141.5 mm (5.57 inch)

Outside diameter ... 54.1 mm (2.13 inch)

(6) 2J-2866 Shim

Thickness ... 0.12 mm (0.005 inch)

Pressure change with one shim ... 242 kPa (35.0 psi)

(7) 3H-2549 Shim

Thickness ... 0.25 mm (0.010 inch)

Pressure change with one shim ... 483 kPa (70.0 psi)

(8) Torque for plug ... 108 ± 14 N·m (80 ± 10 lb ft)

(9) 2J-6089 Spring for pilot valve

Length under test force ... 36.25 mm (1.427 inch)

Test force ... 296 ± 15 N (66 ± 3 lb)

Free length after test ... 44.12 mm (1.737 inch)

Outside diameter ... 12.5 mm (0.49 inch)

(10) Apply 4C-4032 Bearing Mount Compound to the bolt.