Komatsu HM400-1 Dump Truck Service Manual

Table of Contents

00 Index and foreword
01 Specification
10 Structure, function and maintenance standard
20 Standard value table
30 Testing and adjusting
40 Troubleshooting
50 Disassembly and assembly
90 Diagrams and drawings

GENERAL
This section lists the general machine dimensions, performance specifications, component weights, and fuel, coolant and lubricant specification charts.

STRUCTURE, FUNCTION AND MAINTENANCE STANDARD
This section explains the structure and function of each component. It serves not only to give an understanding of the structure, but also serves as reference material for troubleshooting.

TESTING, ADJUSTING AND TROUBLESHOOTING
This section explains checks to be made before and after performing repairs, as well as adjustments to be made at completion of the checks and repairs. Troubleshooting charts correlating Problems to Causes are also mention in this section.

DISASSEMBLY AND ASSEMBLY KOMATSU Dump Truck HM400-1

This section explains the order to be followed when removing, installing, disassembling or assembling each component, as well as precautions to be taken for these operations.

Braking mode:
The shift-down point and the shift-up point are both raised, the engine speed is maintained at a higher level, and the amount of cooling oil for the retarder is ensured to provide greater effect when the engine is used as a brake.
Coasting mode:
The shift-down point and the shift-up point become close to each other to decrease the occurrences of unnecessarily shifting transmission.
Power mode:
The power mode uses the power of the machine to provide the maximum payload. However, when the machine is unloaded or has only a light load (high acceleration), an acceleration sensitive type variable shifting point is used. This detects the acceleration of the machine and shifts the transmission up sooner to provide better acceleration and to improve the fuel consumption, noise, and transmission shock.
Economy mode:
When the machine is being used under light load, such as when traveling unloaded or on flat ground, the shift-up point and shift-down point are both lowered, the engine speed is maintained at a lower level, and the fuel consumption, noise, and transmission shock are improved. In this mode, the maximum engine output is limited.
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