Komatsu WB140-2N and WB150-2N Backhoe Loader Service Manual

Description

Table of Contents

01 GENERAL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 01-1
10 STRUCTURE, FUNCTION AND MAINTENANCE STANDARD . . . . . . . . . . . . . . . . . . . . 10-1
20 TESTING, ADJUSTING AND TROUBLESHOOTING . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20-1
30 DISASSEMBLY AND ASSEMBLY. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30-1
90 OTHER. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 90-1

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 included in this section.

DISASSEMBLY AND ASSEMBLY

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.

When removing covers which are under internal pressure or under pressure from a spring, always leave two bolts in position on opposite sides. Slowly release the pressure, then slowly loosen the bolts to remove.

FLOW VALVE TESTING

1. Disconnect the hose a from the load sensing line. Install the tee b and reconnect the hose.
2. Connect a pressure port and gauge E1 to the tee b.
3. Connect a second gauge E1 to the rear control valve pressure port c.
4. Start the engine and at low idle without any machine movement, check the pressure on both gauges.
• P pressure at control valve gauge: 30 3 kg/cm Normal pressure PLS: 6 2 kg/cm
This value is due to the influence of the counter pressure present in the steering circuit.
• If any variations are found, they do not represent a problem provided that the difference of 21 1 kg/cm between the two readings is respected.
5. If the difference between the readings is higher than 24 1 kg/cm, stop the engine and release the residual pressures.
6. Thoroughly clean the valve d and reinstall it.
Valve = 20 N.M
7. If, after cleaning the valve d, the value still does not fall within the tolerance limits of 24 1 kg/cm, install a new valve.