776D Tractor and 777D and 777D HAA Off-Highway Truck Hydraulic System Caterpillar

Illustration 1	g00626804

Illustration 2	g00626839
Section A-A (A) Idler gear (B) Drive gear

Rotation of the pump is clockwise when the pump is viewed from the drive end.

Type of pump: Gear

Bench test requirements: SAE 10W oil must be stabilized at 66°C (151°F) before the test is performed.

Test at Full Speed:

Output ... 507 L/min (134 US gpm)

Test pressure ... 6900 kPa (1000 psi)

Test speed of pump ... 2000 rpm

(1) Assemble the ring opening over the drain hole.

(2) Assemble the shaft seals with the backs together. The spring loaded members of the shaft seals should be opposite each other.

(3) Torque for eight bolts ... 224 ± 7 N·m (165.2 ± 5.2 lb ft)

(4) Assemble the pressure plates with the chamfer on the discharge side of the pump.

(5) This pump has special Tooth Relief Gears. Assemble these gears so that the rotation arrows on the gears point in the direction that is shown in Illustration 2.