Komatsu 830E-AC Shop Manual page 635

Rear Brake Conditioning
Note: Front brakes
independently from rear brakes in order to control
disc temperatures.
Extreme safety precautions should be used when
making high-energy/high-speed brake stops on
any downgrade. Safety berms or adequate run off
ramps are necessary for any stopping perfor-
mance tests.
1. Temporarily disconnect the FRONT brakes
using the following procedure:
a. Observe safety precautions on the previous
page. Bleed down the steering accumulators
with engine off, and turn the key switch OFF
and wait 90 seconds. Confirm the steering
pressure is released by turning the steering
wheel - No front wheel movement should
occur.
b. Open the two valves (7, Figure 6-38) at the
bottom of the brake accumulators (inside
brake cabinet) to bleed down the two brake
accumulators.
c. Disconnect "BF" hydraulic tube (5, Figure 6-
38) at both ends inside brake control cabinet.
Install a #8, 0.75 x 16UNF-2B, 37° flare Cap
Nut (WA2567, or equivalent) on each fitting
where tube was removed. Tighten caps to
standard torque to prevent leakage. Cap or
plug tube to prevent contamination.
NOTE: This will disconnect the hydraulic
supply from the operator's brake pedal to the
front brakes. There will be a noticeable loss
of "braking action" at the pedal. However,
this method of temporarily disabling the
brakes will still permit the application of
Brake Lock, in the event of an emergency.
d. Close accumulator bleed valves handles (7).
2. Drive empty truck on level terrain at speeds of 5
to 10 MPH while applying (dragging) the brakes
using sufficient pressure to make engine work
until the disc temperatures reach or just exceed
316°C (600°F).
J06025 10/06
will require burnishing
Armature Speed Rear Disc Brakes
NOTE: The Override Switch on the instrument panel
must be depressed and held by the operator in order
to propel the truck with the brakes applied.
Do not exceed 800°F (427°C) disc temperatures
during burnishing.
3. Allow the brake discs to cool to approximately
121°C (250°F) between cycles.
4. Repeat steps 2 and 3.
5. If linings smoke or smell during the second
cycle, continue to repeat burnishing cycle until
smoke and smell are gone or are significantly
reduced.
6. Reconnect front brakes:
a. Relieve pressure
described in Steps 1a and 1b.
b. Remove cap nuts and reinstall tube (5).
Tighten tube nuts to standard torque.
c. Close accumulator bleed valve (7) handles.
7. Start engine and check for leaks.
8. Ensure all brakes are functioning properly and
have cooled to approximately 121°C (250°F)
before releasing truck.
FIGURE 6-38. BRAKE MANIFOLD AND
COMPONENTS
1. "BR" Hydraulic Tube
2. Rear Brake Accu-
mulator
3. Brake Manifold
4. Front Brake Accu-
mulator
in hydraulic system
5. "BF" Hydraulic Tube
6. Brake Lock Shuttle
Valve
7. Brake Accumulator
Bleed Valves
J6-31