Komatsu HD785-5, Operation & Maintenance Manual

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MAINTENANCE
SERVICE PROCEDURE
BLEED AIR FROM REAR BRAKE
WARNING
Stop the machine on level ground and put blocks under the wheels before bleeding the air.
To make it easier to bleed the air, warm the oil up to a temperature
of at least 40
°
C (104
°
F) before bleeding the air.
1. Pull the retarder brake lever, loosen air bleed plug (1) to bleed
the air from the circuit, then tighten plug (1) and release the
retarder brake lever.
2. Repeat this procedure until no more bubbles come out from air
bleed plug (1). After completely bleeding the air, tighten plug
(1) securely.
BLEED AIR FROM FRONT BRAKE
WARNING
Stop the machine on level ground and put blocks under the wheels before
bleeding the air.
1. Start the engine and raise the pressure to the maximum
position in the green range on the air pressure gauge.
2. Fill oil reservoir (1) with oil.
3. Remove the cap of bleeder screw (2), insert a vinyl hose
(inside diameter: 8 mm (0.315in)), then loosen the bleeder
screw approx. 3/4 turns and depress the brake pedal slowly.
After tightening the bleeder screw, release the brake pedal.
Repeat this procedure until no more bubbles come out from the
vinyl hose.
Do not keep the brake pedal depressed continuously. Depress
it each time slowly to bleed the air.
After bleeding the air, tighten bleeder screw (2) securely and fit
the cap.
4. After completion of the air bleeding procedure, fill the oil reservoir to the specified level (MAX).
Repeat the same procedure on the left and right sides.
When bleeding the air from the front brakes and rear brakes at the same time, bleed the air from the rear brakes first.
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