793B Off-Highway Truck Air System and Brakes Service and Parking Brake (Front) Caterpillar

Illustration 1	g00294219

Illustration 2	g00103659
Section A-A

Illustration 3	g00103660
Section B-B

(1) When you assemble the wheel to the machine, the purge screws and the adapters will be in the rear set of ports and in the top set of ports.

(2) Torque for the 44 bolts ... 500 ± 50 N·m (370 ± 37 lb ft)

(3) Torque for the eight studs ... 100 ± 15 N·m (75 ± 11 lb ft)

(4) Torque for the eight nuts ... 270 ± 25 N·m (200 ± 18 lb ft)

Note: Torque each nut (4) by one revolution to evenly pull down the housing. When all the nuts bottom out, tighten the nuts to the specified torque in the letter sequence that is provided in illustration 1.

(5) When you assemble the wheel to the machine, the plugs will be in the bottom ports.

Note: Rubber toric seals and all the surfaces that come in contact with the rubber toric seals must be clean at the time of assembly. Allow rubber toric seals and all the surfaces that come in contact with rubber toric seals to dry before the time of assembly. Immediately before assembly, put a small amount of oil on any surfaces that contact the rubber toric seals. Seal rings must be assembled squarely with the bore. Rubber toric seals should not be twisted. Do not allow the rubber toric seals to bulge.

(6) Torque for the 12 studs ... 100 ± 15 N·m (75 ± 11 lb ft)

(7) Torque for the 12 nuts ... 270 ± 25 N·m (200 ± 18 lb ft)

Note: Torque each nut (7) by one revolution to evenly pull down the housing. When all the nuts bottom out, tighten the nuts to the specified torque in a crisscross pattern.

(8) Assembled brake pack

Thickness of ten new discs, nine new plates, and two new damper assemblies ... 86.24 ± 1.88 mm (3.395 ± .074 inch)

Thickness of one new 7T-2815 Friction Disc ... 5.08 ± 0.08 mm (0.200 ± 0.003 inch)

Thickness of one new 8W-0212 Plate ... 2.413 ± 0.064 mm (0.0950 ± 0.0025 inch)

Thickness of one new 6G-6500 Damper Assembly ... 6.86 ± 0.25 mm (0.270 ± 0.010 inch)

Note: Install the damper assembly so that the facing material faces toward the plate and the piston.

Note: At assembly, lubricate the friction discs with the oil that is used in the brakes. See the Operation and Maintenance Manual, "Lubricant Viscosities"
for that information.

(9) Torque for the 44 bolts ... 500 ± 50 N·m (370 ± 37 lb ft)

(10) 9D-6093 Spring (outer)

Quantity ... 46

Test length ... 90.5 mm (3.56 inch)

Test force ... 4235 ± 254 N (952 ± 57 lb)

Free length after test ... 116.5 mm (4.59 inch)

Outside diameter ... 46.02 mm (1.812 inch)

(11) 9D-6135 Spring (inner)

Quantity ... 42

Test length ... 90.50 mm (3.563 inch)

Test force ... 1535 ± 44 N (345 ± 10 lb)

Free length after test ... 115.49 mm (4.547 inch)

Outside diameter ... 26.59 mm (1.047 inch)

(12) 9D-9121 Spring (return)

Quantity ... 4

Test length ... 74.90 mm (2.949 inch)

Test force ... 890 ± 27 N (200 ± 6 lb)

Free length after test ... 91.13 mm (3.588 inch)

Outside diameter ... 26.59 mm (1.047 inch)