NorAM 65E Turbo Motor Grader, Service Manual

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65E Turbo Motor Grader
Service Manual
6 - 11 Service 2.00_2013.03
Section 6
Rear Axle and Tandem
The service brake hydraulic system is divided into sepa -
rate circuits for the right and left brakes, with two sepa -
rate reservoirs supplying the master cylinder. The circuits
are connected when at rest to vent pressure from the
system.
As pressure develops, the circuits are separated. The
larger piston acts on one circuit and moves the second,
smaller piston. Pressure in each circuit is the same once
the first piston has created at least 10 bar (145 psi). If the
first circuit should fail, the first piston pushes directly on
the second, creating pressure but a greater force is
required.
A pressure differential switch monitors the pressure in
each circuit to ensure equal braking pressure on each
side. If pressure drops in one circuit, a spool in the switch
shifts toward that side, closing the circuit. A warning lamp
illuminates on the front monitor to alert the operator that
pressure is not equal in the brake circuits.
The parking brake is a cable - operated, disk - type brake
located on the rear output shaft of the transmission. The
disk is splined to the output shaft. Brake pads on the
brake caliper expand when the ratcheting lever in the cab
is pulled, preventing rotation of the output shaft and
machine.
The transmission is equipped with a disconnect feature
which dumps oil to the transmission sump when acti
-
vated. The transmission disconnect is always activated
when the parking brake lever is pulled.
The disconnect feature is also activated when the brake
pedal is depressed if the transmission inching control
switch on the right side console is off. If the inching con
-
trol switch on the right side console is on, the transmis -
sion will continue to operate, driving the grader wheels
unless the brakes are applied with sufficient force to
overcome the engine torque.
Specifications
Service Brake
Type. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Single Disc in Oil Bath, Integral to Rear Axle
Number of Discs per Side . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
Friction Disc Thickness (Nominal) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.512 in. (13 mm)
Minimum Friction Disc Thickness . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.394 in. (10 mm)
1. Master Cylinder
2. Brake Fluid Reservoirs
3. Two brake groups located inside axle.