Komatsu HM400-1, Manual

Page: 240 / 258

.
MAINTENANCE
SERVICE PROCEDURE
CHECK WEAR OF BRAKE DISC
WARNING
Carry out this check when the brake oil temperature is below 60
°
C (140
°
F).
If the disc wear approaches the wear limit, check the condition frequently, regardless of the maintenance interval. In addition,
check the retarder capacity carefully.
1. Stop the machine on level ground, set the parking brake switch to the PARKING position, then check that the
other brakes are not applied before starting inspection.
2. Turn the starting switch ON and check that the retarder oil pressure caution lamp is out.
If the retarder oil pressure caution lamp is lighted up, start the engine, run the engine at 2000 rpm, and if the lamp
goes out, turn the starting switch OFF.
3. Remove cap nut (1).
4. Depress the brake pedal, keep it depressed, and push in the
rod (2) of the gauge until contacts the piston.
5. If mark (3) at position "A" of rod (2) enters beyond guide end
face (4), it means that the disc has reached the wear limit.
If the disc has reached the wear limit, please contact your
Komatsu distributor for inspection and maintenance.
6. Tighten cap nut (1) removed in Step 3.
Tightening torque: 14.7 to 19.6 N
·
m
(1.5 to 2.0 kgf
·
m, 10.8 to 14.5 lbft)
REMARK
With new machines, the position of the guide is adjusted so that mark (5) comes to end face (4) of the guide, so
do not loosen locknut (6) except when replacing the disc.
Carry out the operation with two workers. One worker depresses the brake pedal and the other pushes in the
rod.
If the rod is pushed in when the engine is running, the rod will be pushed back by the brake cooling oil pressure,
so always carry out this operation with the engine stopped.
There are marks on the rod at three places (A, B, C), but on this machine, use the mark at position A.
CHECK TIGHTENING PARTS OF TURBOCHARGER
Contact your Komatsu distributor to have the tightening portions checked.
4 - 62