PDF Shop Manual Komatsu WA500-7 Wheel Loader - 3 MB
This is the official shop manual for the Komatsu WA500-7 Wheel Loader.
It contains complete instructions for testing, adjusting, disassembly, and assembly of the machine.
This highly detailed manual is intended for trained and qualified service technicians.
It is the definitive resource for performing any repair or maintenance procedure to factory standards.
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--- Page 1 ---
SEN05693-03
WHEEL LOADER WA500 -7
SERIAL NUMBERS 10001 and up
--- Page 3 ---
00 Index and foreword
Foreword, safety and general information
Fire prevention (ALL-0000-001-K-27-A)
Action if fire occurs (ALL-0000-17A-K-01-A)
• Turn the starting switch to the OFF position to
shutdown the engine.
• Use the handrails and steps to get off the
machine.
• Do not jump off the machine. You may fall or
suffer serious injury.
• The fume generated by a fire contains harmful
materials which have a bad influence on a
human body when they are sucked.
Don't breathe a fume.
• After a fire, there may be harmful compounds
left. If it touches your skin it may have a bad
influence on your body.
Be sure to wear rubber gloves when handle the
materials left after the fire.
The material of the gloves, which is
recommended is polychloroprene (Neoprene) or
polyvinyl chloride (in the lower temperature
environment).
When wearing cotton-work-gloves, wear rubber • Fire caused by accumulation or attachment
gloves under them. of flammable material
• Remove any dry leaves, chips, pieces of
Prevent fire (ALL-0000-17B-K-03-A) paper, coal dust, or any other flammable
• Fire caused by fuel, oil, coolant or window materials accumulated or attached to or
washer fluid around the engine exhaust manifold, muffler,
Do not bring any flame or fire close to flammable or battery, or on the undercovers.
substances such as fuel, oil, coolant or window • To prevent fires from being caught, remove
washer fluid.There is danger that they may catch any flammable materials such as dry leaves,
fire. Always observe the following. chips, pieces of paper, coal dust, or any
• Do not smoke or use any flame near fuel or other flammable materials accumulated
other flammable substances. around the cooling system (radiator, oil
• Shut down the engine before adding fuel. cooler) or on the undercover.
• Do not leave the machine when adding fuel • Fire coming from electric wiring
or oil. Short circuits in the electrical system can cause
• Tighten all the fuel and oil caps securely. fire. Always observe the following.
• Be careful not to spill fuel on overheated • Keep all the electric wiring connections clean
surfaces or on parts of the electrical system. and securely tightened.
• After adding fuel or oil, wipe up any spilled • Check the wiring every day for looseness or
fuel or oil. damage. Reconnect any loose connectors or
• Put greasy rags and other flammable refasten wiring clamps. Repair or replace any
materials into a safe container to maintain damaged wiring.
safety at the workplace. • Fire caused by piping
• When washing parts with oil, use a non- Check that all the clamps for the hoses and
flammable oil. Do not use diesel oil or tubes, guards, and cushions are securely fixed
gasoline.There is danger that they may catch in position.
fire. If they are loose, they may vibrate during
• Do not weld or use a cutting torch to cut any operation and rub against other parts. There is
pipes or tubes that contain flammable liquids. danger that this may lead to damage to the
• Determine well-ventilated areas for storing oil hoses and cause high-pressure oil to spurt out,
and fuel. Keep the oil and fuel in the leading to fire and serious personal injury or
specified place and do not allow death.
unauthorized persons to enter. • Fire around the machine due to highly heated
• When performing grinding or welding work exhaust gas
on the machine, move any flammable This machine is equipped with KDPF (Komatsu
materials to a safe place before starting. Diesel Particulate Filter).
00-24 WA500-7
--- Page 4 ---
00 Index and foreword
Foreword, safety and general information
If the part is not under hydraulic pressure, the following corks can be used.
Dimensions
Nominal No. Part No.
D d L
06 07049-00608 6 5 8
08 07049-00811 8 6.5 11
10 07049-01012 10 8.5 12
12 07049-01215 12 10 15
14 07049-01418 14 11.5 18
16 07049-01620 16 13.5 20
18 07049-01822 18 15 22
20 07049-02025 20 17 25
22 07049-02228 22 18.5 28
24 07049-02430 24 20 30
27 07049-02734 27 22.5 34
Precautions for installation work
• Tighten all of the bolts and nuts (sleeve nuts) to the specified torque (KES).
• Install the hoses without twist and interference, and securely fasten the clamps located in-between if they
are.
• Replace all of the gaskets, O-rings, cotter pins, and lock plates with new parts.
• Bend the cotter pins and lock plates securely.
• When applying adhesive, clean and degrease the part, and apply two to three drops of adhesive to the
threaded portion.
• When applying liquid gasket, clean and degrease the surface, and apply it uniformly after making sure that
the surface is free from dirt or damage.
• Clean all of the parts, and correct any damage, dents, burrs, or rust found on them.
• Coat the rotating parts and sliding parts with engine oil.
• Coat the surfaces of the press-fitting parts with molybdenum disulfide lubricant (LM-P).
• After installing the snap ring, check that the snap ring is settled in the ring groove completely.
• When connecting wiring harness connectors, clean the connectors to remove oil, dirt, or water, then
connect them securely.
• Use the eye bolts with no fatigue and deformation and screw them in securely. Match the directions of the
eyes and the hook.
• When installing split flanges, tighten the bolts uniformly and alternately to prevent excessive tightening on
one side.
a When the hydraulic cylinder is used for the first time after reassembly of the hydraulic equipment such as
the hydraulic cylinder, pump, etc. and piping after removing them for repair, be sure to perform air bleeding
of the hydraulic circuit according to the following procedure.
1. Start and run the engine at low idle.
2. Repeat the operation to extend and retract each cylinder of the work equipment to approximately 100
mm before the stroke end four to five times.
3. Operate the hydraulic cylinder three to four times to the end of its stroke.
WA500-7 00-49
--- Page 5 ---
01 Specification
Specification
Engine
Machine model WA500-7
Serial number 10001 and up
Model SAA6D140E-6
4-cycle, water-cooled, in-line vertical, direct injection,
Type with turbocharger, air-cooled aftercooler, and cooled
EGR
No. of cylinders – bore x stroke mm 6 - 140 x 165
Total piston displacement l {cc} 15.2 {15,240}
Flywheel horsepower
• SAE J1995[Gross](*1) 266 {357}/1,900 {1,900}
Performance (In P mode)
kW {HP}/min-
• ISO 14396 1 {rpm} 266 {357}/1,900 {1,900}
• ISO 9249/SAE J1349[Net](*2) 263 {353}/1,900 {1,900}
Nm {kgm}/
Max. torque (*1) 1,784 {182}/1,250 {1,250}
min-1 {rpm}
Fuel consumption ratio at rated g/kWh
221 {162}
horsepower {g/HPh}
Max. speed with no load min-1 {rpm} 2,120 {2,120}
Min. speed with no load min-1 {rpm} 790 {790}
Min. low idle (*4) min-1 {rpm} 700 {700}
Starting motor 24 V, 11 kW
Alternator 24 V, 90 A
Battery (*3) 24 V, 136 Ah (165 G51), 2 pieces
Power train
Machine model WA500-7
Serial number 10001 and up
Torque converter 3-element, 1-stage, 2-phase
Planetary type, multiple disc type, 4 forward/reverse
Transmission gear speed type
Reduction gear Spiral bevel gear, splash lubrication type
Differential Straight bevel gear type
Single reduction planetary gear, splash lubrication
Final drive type
*1: Indicates the value of the basic engine (without cooling fan).
*2: Indicates the value at the minimum cooling fan speed.
*3: The battery capacity (Ah) is indicated in the 5-hour rate.
*4: Indicates the low idle speed when the work equipment control lever is in NEUTRAL for at least 10 seconds
while the auto-decelerator setting is ON and the directional lever is in NEUTRAL.
a The engine flywheel horsepower is indicated in the net value and gross value. The gross denotes the
flywheel horsepower measured on the basic engine unit, while the net denotes the value measured of an
engine under the condition essentially the same as that when it is installed on a machine.
a Following shows the flywheel horsepower (net) at the maximum cooling fan speed.
250 kW {335 HP}/1,900 min-1 {rpm}
01-8 WA500-7
--- Page 6 ---
10 Structure and function
EGR cooler
EGR cooler (ENG125-A9L0-041-K-00-A)
a The shape is subject to machine models.
1. Header plate
4. Shell
A: EGR gas inlet
B: EGR gas outlet (to EGR valve)
C: Coolant inlet
D: Coolant outlet
E: Air vent
F: Air vent
2. Flat tube
3. Inner fin
Operation (ENG125-A9L0-044-K-00-A)
• The EGR gas enters from (A) and flows through 9 flat tubes (2).
WA500-7 10-17
--- Page 7 ---
10 Structure and function
Cooling fan motor
Cooling fan motor (WA380-B5L0-041-K-00-A)
P: From fan pump
T: To oil cooler
TC: To hydraulic tank
10-42 WA500-7
--- Page 8 ---
10 Structure and function
Transmission
3. Transmission
4. Emergency steering pump mounting location
5. Oil filler pipe mounting location
6. Speed sensor
7. Transmission control valve
8. Torque converter drain tube mounting location
9. Drain valve
10. Drain plug
11. Transmission lubricating oil temperature sensor
12. Strainer
WA500-7 10-67
--- Page 9 ---
10 Structure and function
Forward and reverse clutch ECMV and gear speed clutch
ECMV
Filling phase (range B in chart)
• When the current flows to proportional solenoid (1) while there is no oil in the clutch, the hydraulic force
balanced with the solenoid force is applied to chamber (B) to push pressure control valve (3) to the left. As
a result, the oil flows into the clutch chamber through pump port (P) and orifice (a) of flow detecting valve
(4). At this time, differential pressure is caused between the upstream and downstream across the orifice
(a) of flow detecting valve (4). This differential pressure pushes flow detecting valve (4) to the left.
When the clutch chamber is filled with the oil and the oil does not flow from pump port (P) to clutch port (A)
any more, the differential pressure over orifice (a) of flow detecting valve (4) is lost and the oil pressure
pushes flow detecting valve (4) to the right, and fill switch (5) is turned "ON".
10-92 WA500-7
--- Page 10 ---
10 Structure and function
Differential
<Mechanism of generating braking torque to right and left side gears (6)>
Shaft (7) is supported on the cam surfaces made on the surfaces of pressure rings (4) that are facing each
other. The power (= torque) from pressure rings (4) is transmitted to shaft (7) through the cam surfaces. Force
Fa to separate right and left pressure rings (4) is generated by inclination of the cam surfaces in proportion to
the transmitted torque.
This separating force (Fa) acts on the brakes on the back of right and left side gears (6) to generate braking
torque.
<When machine is traveling straight>
1. When the driving forces of the right and left wheels are balanced
[When road conditions (friction coefficient) under the right and left wheels and the wheel loads are even and
the center of load on the bucket is not shifted]
The power from the transmission is distributed evenly by the differential gear to the right and left. Since the
wheel slip limits on the right and left sides are the same under this condition, both wheels slip and the
differential does not operate even if the power from the transmission exceeds the wheel slip limit.
No load is applied to the brake on the back of each side gear.
WA500-7 10-117
--- Page 11 ---
10 Structure and function
Steering control valve
When machine turns to left
• When the steering wheel is turned to the left, the orbit-roll valve operates and steering spool (2) moves to
the right.
The oil from the steering pump flows into port (A), and then flows through control spool (1) into steering
spool (2), push opens load check valve (5) of the spool, and flows into the rod side of the L.H. cylinder and
into the bottom side of the R.H. cylinder to turn the machine to the left.
• The return oil from the the right and left cylinders is drained through the passage inside steering spool.
Steering relief valve (WA500-F590-041-K-00-A)
1. Adjustment screw
2. Spring
10-142 WA500-7
--- Page 12 ---
10 Structure and function
Charge valve
• When the pressure in port (ACC1) is higher than the pressure in port (ACC2), shuttle valve (1) moves to
the left to disconnect port (ACC1) and oil passage (B).
• The open area between port (ACC2) and oil passage (B) increases and the oil is supplied to the
accumulator on the port (ACC2) side.
• When the pressure in port (ACC2) is higher than port (ACC1), the oil is supplied to the accumulator on the
port (ACC1) side.
• The pressurized oil from the pump is supplied first to the lower pressure circuit of the two systems.
WA500-7 10-167
--- Page 13 ---
10 Structure and function
Hydraulic component layout
1. Control valve
2. Bucket cylinder
3. Accumulator (for PPC circuit)
4. Charge valve
5. Work equipment pump
6. Cooling fan pump
7. Steering pump
8. Steering control valve
9. 2-spool gear pump (power train charge pump (1) and power train charge pump (2))
10. Steering cylinder
11. Lift cylinder
12. Accumulator (for ECSS)
13. Hydraulic tank
14. Hydraulic oil cooler
15. Cooling fan motor
10-192 WA500-7
--- Page 14 ---
10 Structure and function
Work equipment pump
WA500-7 10-217
--- Page 15 ---
10 Structure and function
Hydraulic circuit diagram and names of valves
• When the pressure in actuator circuit (B) increases to the necessary pressure, pump discharge pressure
(PPS) increases.
• Check valve (5) in main spool (2) opens and the high pressure oil of LS circuit (PLS) flows into actuator
circuit (B).
• The pressure in LS circuit (PLS) becomes almost the same as that in actuator circuit (B).
LS bypass valve (WA500-PQH2-041-K-00-A)
1. Hydraulic pump
2. Main spool
3. Pressure compensation valve
4. LS shuttle valve
5. LS bypass valve
6. LS circuit
Function (WA500-PQH2-042-K-00-A)
• This valve releases the remaining pressure in LS pressure circuit (6) through orifices (a) and (b).
• This valve decreases the rising speed of the LS pressure to prevent a sudden change of the oil pressure.
• Since the oil flows through LS valve (5), pressure loss is made by the circuit resistance between throttle
(c) of main spool (2) and LS shuttle valve (4).
• The effective LS differential pressure decreases to improve the dynamic stability of the actuator.
10-242 WA500-7
--- Page 16 ---
10 Structure and function
Parking brake control system
• When parking brake switch (2) is turned "OFF" (releasing), no current flows in parking brake relay (1) and
the relay contacts are open.
• Even if starting switch is turned to the "ON" position, no current flows to parking brake solenoid valve (3).
Accordingly, the parking brake is not released automatically.
When auto-idle stop operates
• If parking brake switch (2) is turned to the "OFF" (releasing) position while the starting switch is in the "ON"
position, the current from the battery relay flows through parking brake relay (1), parking brake switch (2),
and auto-idle stop parking brake relay (5) to parking brake solenoid valve (3), thus the parking brake is
kept released.
• When the auto-idle stop operates, transmission controller (4) outputs a current to auto-idle stop parking
brake relay (5).
• The current flows in the coil of auto idle stop parking brake relay (5) and the contacts open.
• No current flows in parking brake solenoid valve (3), and the parking brake is applied.
• When the auto-idle stop operates, the parking brake also operates automatically and keeps operating
during restarting operation.
WA500-7 10-267
--- Page 17 ---
10 Structure and function
Transmission controller system
Range A: Engine speed < 500 rpm (Engine "stopped" to "being cranked")
• The target fan speed is set to 0 rpm to reduce the torque required to start the engine and for higher engine
startability.
Range B: 500 rpm < Engine speed Z 740 rpm (Engine being cranked)
• During cranking for starting the engine, the fan target speed is set to 100 rpm to reduce the torque
required to start the engine and improve the engine startability.
Range C: Basic control (740 rpm < Engine speed)
• The ordinary fan control based on "Fan speed set by temperature" is performed.
Control function when brake accumulator is charged (WA500-B71B-042-K-00-A)
• The fan pump is used for charging the brake accumulator as well.
• While the brake accumulator is being charged, the charge time is shortened and the control is performed
differently from the normal control by temperature to prevent the fan from stopping during the charge.
• For 10 seconds after the brake accumulator pressure drop signal is turned OFF, the minimum fan speed is
set to 620 rpm.
• If the brake accumulator pressure is turned OFF, the minimum fan speed is 620 rpm for 10 seconds after
the control at the start of the engine is finished.
Fan reverse function (WA500-B715-042-K-00-A)
• When the manual fan reverse mode is operated through the machine monitor to clean the radiator core,
the cooling fan reverse rotation solenoid valve of the cooling fan motor operates to reverse the fan
rotation.
Fan auto reverse function
1. Fan rotation manual reverse function
• The operator can change the fan rotation direction freely by setting the manual fan reverse mode to the
"Reverse" or "Forward" position.
• While the fan rotation direction is being changed, the pilot lamp is in changing displayed on the
standard screen to notify the operator of the operating condition. If the changing condition is not
satisfied because of high temperature of the coolant or oil, the pilot lamp which indicates that the
satisfaction of the condition is waited lights up.
• On the standard screen, the cooling fan reverse rotation pilot lamp indicates the fan reverse rotation
condition.
When all the conditions are satisfied, the fan rotation direction is changed from "Forward" to "Reverse".
Condition 1 The manual fan reverse rotation mode is set to "Reverse".
The coolant temperature is below 102 °C.
Condition 2
[for prevention of overheat]
The hydraulic oil temperature is below 97 °C.
Condition 3
[for prevention of overheat]
The torque converter oil temperature is below 120 °C.
Condition 4
[for prevention of overheat]
At least 10 seconds elapse after the brake accumulator pressure drop signal is turned OFF.
Even if the accumulator pressure drop signal turns OFF at least 10 seconds elapse after the
Condition 5 engine is started.
[For securing oil quantity to be added to the brake accumulator]
Condition 6 There is no error in the fan speed sensor or engine speed sensor.
When any of the conditions is satisfied, the fan rotation direction is changed from "Reverse" to "Forward".
The manual fan reverse rotation mode is set to the "Forward" position while the fan is rotating
Condition 1
in reverse.
Condition 2 10 minutes elapse with the fan rotating in reverse.
Condition 3 An error is detected in the fan reverse rotation solenoid or fan pump EPC solenoid.
Condition 4 The engine stops.
2. Fan rotation auto reverse function
• The fan rotation reverse cycle and fan reverse rotation duration can be set at a certain interval by
setting the auto-fan rotation reverse mode through the machine monitor.
10-292 WA500-7
--- Page 18 ---
10 Structure and function
Work equipment control system
• A bucket automatic operation pattern matched to the working cycle and load is selected.
Mode selection
No. Objective material Mode
1 Gravel/Sand LOOSE mode
2 Quarry/Blasted rocks ROCK mode
1. Condition for starting semi auto-digging
The semi auto-digging is ready when following (1) to (4) are satisfied.
(1) Semi auto-digging is set in "ROCK" or "LOOSE" mode.
(2) Machine is traveling forward (There is F signal)
Condition 1 (3) Boom angle is less than -30 ° (almost on ground)
(4) Kickdown switch is operated
a Even during work in 1st gear speed, semi auto-digging does not start if kickdown
switch is not operated.
Semi auto-digging (auto tilt) starts when following (1) and (2) are satisfied.
Condition 2
(1) Boom is raised after condition 1 is satisfied.
WA500-7 10-317
--- Page 19 ---
10 Structure and function
Machine monitor system
Monitor Item Display
display displayed Contents Remarks
color
Semi-auto Lights up while machine is digging in
Digging Green
semi-auto mode.
Multi-
coupler
lock Lights up when multi-coupler lock is
Red
release (if released.
equipped)
Lights up when directional selector
Green
switch is effective.
Directional
selection Lights up when wrong operation is
Yellow
made.
Green Lights up when joystick is effective.
Joystick Lights up when wrong operation is
Yellow
made.
E.C.S.S. Green Lights up when ECSS is effective.
Green Lights up when throttle lock is set.
Throttle Lights up when throttle lock is
lock Yellow canceled temporarily or in auto-
deceleration mode.
Lights up when raise stop is set.
Remote
Green Lights up when lower stop is set.
positioner
Lights up when raise and lower
stops are set.
Work
Lights up when work equipment is
equipment Red
locked.
lock
Auto-shift Green Lights up when auto-shift operates.
• Lights up when transmission cut-
Transmis- off operates.
Green • Flashes when resetting is
sion cut-off
acceptable.
10-342 WA500-7
--- Page 20 ---
10 Structure and function
System component parts
Pin No. Signal name Input/output signal
76 (*1) ―
77 (*1) ―
78 (*1) ―
79 (*1) ―
80 (*1) ―
81 (*1) ―
*1: Never connect these pins. Malfunctions or failures may occur.
AMP-40P [CN-MCM1 B]
Pin No. Signal name Input/output signal
82 Switch panel built-in buzzer Output
83 (*1) ―
84 (*1) ―
85 (*1) ―
86 Load meter printer BUSY Input
87 (*1) ―
88 (*1) ―
89 CAN-L (KOMNET/c) Input/Output
90 (*1) ―
91 Caution LED power supply Output
92 (*1) ―
93 (*1) ―
94 Load meter printer GND ―
95 (*1) ―
96 (*1) ―
97 CAN-H (KOMNET/c) Input/Output
98 Continuous power supply (5.6 V) Output
99 GND ―
100 (*1) ―
101 (*1) ―
102 Load meter printer TX Output
103 (*1) ―
104 (*1) ―
105 CAN-L (KOMNET/r) Input/Output
106 External starting signal Input
107 Power supply (12 V) Output
108 LIN Input/Output
109 (*1) ―
110 (*1) ―
111 (*1) ―
112 CAN-H (KOMNET/r) Input/Output
113 CAN-H (KOMNET/r) Input/Output
114 (*1) ―
115 (*1) ―
116 (*1) ―
117 (*1) ―
118 (*1) ―
119 (*1) ―
120 (*1) ―
121 (*1) ―
*1: Never connect these pins. Malfunctions or failures may occur.
JAE-8P [CN-MCM2]
WA500-7 10-367
--- Page 21 ---
10 Structure and function
Sensor
Function (ENG125-AG62-042-K-00-A)
• Like the NE speed sensor, it utilizes 0 to 5 V pulses that result from the change in the magnetic lines
passing through the sensor.
• The disc gear installed to the central part of the camshaft of the high-pressure pump has teeth (cut parts)
around it at intervals of 120 deg.
• In addition to the above teeth, one more tooth is installed. Accordingly, seven pulses are generated every
two revolutions of the engine.
• The standard pulse of No. 1 cylinder is recognized by the combination of the NE speed sensor pulse and
Bkup speed sensor pulse.
Common rail pressure sensor (ENG-AE28-041-K-00-A)
1. Connector
2. Sensor
Function (ENG-AE28-042-K-00-A)