Galeo HD785-7 DUMP TRUCK. Operation and Maintenance Manual (2006)

OPERATION

METHOD OF INCREASING SET TRAVEL SPEED

If it is desired to increase the set speed, depress the accelerator pedal to increase speed, and when the desired set
travel speed is reached, press the set switch on the auto retarder (ARSC) set lever. The set travel speed will be
changed to the new speed.

METHOD OF DECREASING SET TRAVEL SPEED

If it is desired to decrease the set speed, operate the retarder control lever to reduce speed, and when the desired
set travel speed is reached, press the set switch on the auto retarder (ARSC) set lever. The set travel speed will be
changed to the new speed.

REMARK

After using the retarder control lever to reduce the speed, return it to its original position.
If the lever is operated suddenly, the brakes will be applied suddenly.

SAVING SET TRAVEL SPEED

If the machine starting switch is turned OFF or the auto retarder (ARSC) switch is turned OFF, the set travel speed
remains in the memory. When the starting switch is turned ON or the auto retarder (ARSC) switch is turned ON, the
previous set speed is displayed again on the auto retarder set speed indicator.

TRAVELING AGAIN AT SET TRAVEL SPEED

If the machine repeatedly travels on the same slope, once the travel speed has been set, it is possible to operate
the ARSC without carrying out the setting operation each time.
Before entering a downhill slope, if the travel speed has been adjusted to a speed lower than the set speed displayed
on the auto retarder set speed indicator, the auto retarder READY pilot lamp lights and the ARSC is actuated when
the accelerator pedal is released.

REMARK

When traveling at a speed greater than the set speed displayed on the auto retarder set speed indicator, the ARSC
is not actuated even when the accelerator pedal is released. When this happens, the auto retarder READY pilot
lamp also does not light up. Always adjust the travel speed to a speed lower than the set speed displayed on the
auto retarder set speed indicator, and check that the auto retarder READY pilot lamp lights up.

Before starting down the hill, check that a suitable set speed is displayed on the auto retarder set travel speed
indicator and that the auto retarder READY pilot lamp is lighted up.

METHOD OF CANCELING SET TRAVEL SPEED

Method 1: If the cancel operation is carried out for more than 1 second, the control is stopped. When this happens,

the auto retarder set speed indicator shows 0.

Method 2: If the auto retarder (ARSC) switch is turned OFF, the control is canceled. When this happens, the auto

retarder set speed indicator goes out.

REMARK

For Method 1, cancel operation must be continued for at least 1 second (different from other switches) to cancel the
control. This is to prevent any problem of the control being canceled if the switch is touched by mistake.

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OPERATION

BRAKE PERFORMANCE CURVE

Method of using graph
Example: Machine equipped with exhaust brake

Downhill distance: 1500 m (4921 ft)
Travel resistance: -11% [grade resistance: -13%, rolling resistance: 2%]
Load: 91ton

Obtain the maximum permissible speed and the transmission speed range from the graph when traveling downhill
under the above conditions.

1. Use the brake performance graph for the downhill distance of 1500 m (4921 ft).
2. Starting from point (A) which corresponds to the overall weight of the machine, draw a perpendicular line down.
3. Take the point where it crosses the line for travel resistance -11% as (B) and draw a horizontal line.
4. Take the point where it crosses the performance curve as (C), and draw a perpendicular line down. Take the

point where this line crosses the travel speed scale as (D).

5. The following information can be obtained from this procedure.

From point (D): Maximum permissible speed = 30 km/h (18.6 MPH)
From point (C): Speed range = F4

This maximum permissible speed is one guideline determined from the retarder brake performance, so on an actual
jobsite, determine a safe downhill travel speed (below the maximum permissible speed) to match the conditions of
the jobsite so that the retarder brake oil temperature gauge is always in the green range.

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OPERATION

STEERING THE MACHINE

WARNING

If the machine is turned at high speed or on a steep slope, there is danger
that it will turn over, so do not operate the steering in such conditions.

CAUTION

Do not continue to apply force to the steering wheel when it has been
turned fully to the left or right. This will make the oil temperature in the
circuit rise and will cause overheating.

To turn the machine when traveling, turn steering wheel (1) in the direction of the turn.
When traveling around a curve, release the accelerator pedal before entering the curve, shift down to a lower speed
range, then depress the accelerator pedal to travel around the curve. Never coast around the curves at high speed.

REMARK

The angle of the steering wheel may change (the position of the spoke may change slightly) when the machine
is traveling, but this is not a failure.
If force is applied to the steering wheel when the tires have been turned fully to the left or right, the steering wheel
will turn a little at a time, but this is not a failure.

LOADING OPERATIONS

When using a large wheel loader to load large rocks, if the rocks are loaded directly into the dump body parts of the
dump body may be deformed. To prevent this, when loading large rocks, first load sand or soil to act as a cushion,
then load the rocks on top of this to reduce the impact on the dump body.
In addition, when loading rocks that exceed the following conditions, install the optional dump body reinforcement
plate.

Rocks with one side over 0.5 m (1 ft 8 in)
Rocks of hardness more than 4.5 (Mohs scale)
Rocks with a weight of more than 300 kg (662 lb)
When transporting steel ingots

For the types and the selection of the dump body, see "SELECTING DUMP BODY (PAGE 6-2)".

NOTICE

When traveling, always set the dump lever to the FLOAT position regardless of whether the dump body is empty or loaded.
If the dump lever is not at the FLOAT position and the shift lever is not at the N position, the central warning lamp will flush and
the alarm buzzer will sound.

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OPERATION

DUMP OPERATIONS

WARNING

When dumping a load, always carry out the dumping operation in
accordance with the signals from the flagman.
When dumping large rocks, operate the dump body slowly.
Do not load the dump body while it is still raised.
When carrying out inspection with the dump body raised, always use
the body pivot pins, set the dump lever to the HOLD position and lock
it securely. For details, see "BODY PIVOT PIN (PAGE 3-46)".

Operate the dump body as follows.

1. Place shift lever (1) at the N position, and set parking brake

switch (2) to the PARKING position.

2. Move dump lever (3) to the RAISE position, then depress the

accelerator pedal to raise the dump body.
If the dump lever is released when it is at the RAISE position,
it is held at the RAISE position and the dump body will continue
to rise.
The dumping speed increases in proportion to the engine
speed.

3. When the dump body rises to the previously set position, dump

lever (3) returns to the HOLD position. The dump body is held
at that position.
If it is necessary to raise the dump body further, operate dump
lever (3) to the RAISE position and the dump body will rise. If
dump lever (3) is released, dump lever (3) will return to the
HOLD position and the dump body will stop at that position.

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OPERATION

4. When dump lever (3) is moved to the LOWER position, the

dump body will start to move down.

5. When the dump body has moved down a certain distance,

move dump lever (3) to the FLOAT position. (When the lever is
released, it will return to the FLOAT position.) The dump body
will then move down under its own weight.

NOTICE

If the dump control lever is not at the FLOAT sign position or the gear
shift lever is not at the N position, the central warning lamp will light up
and the alarm buzzer will sound.
With the auto emergency steering system, if the warming-up operation
has not been carried out thoroughly and the parking brake switch is set
to TRAVEL, the emergency steering may be actuated momentarily when
the dump control lever is operated.
When raising the dump body, to prevent any impact load on the
hydraulic circuit or hoist cylinder, let the accelerator pedal back when
the dump body is near the maximum angle.
Regardless of the speed range set by the gearshift lever, the speed
range is set to 1st if the dump body is raised. Always keep the dump
body lowered when traveling.

The dump control is carried out electrically. If there is any problem in the sensors or valves, a failure code is
displayed and the dump body is held in position. If it is desired to move the dump body forcibly for inspection or
repair, please ask your Komatsu distributor to carry out the operation.

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OPERATION

PRECAUTIONS FOR OPERATION

When traveling on roads in rain or snow, or when traveling on muddy or soft ground, consider the loaded condition
of the machine and be extremely careful not to let the tires slip or the machine spin and sink into the ground.
If the engine should stop when the machine is traveling, stop the machine immediately, then move the gear shift
lever to the N position, and start the engine again.
If the central warning lamp and pilot lamp for any EMERGENCY item on the machine monitor should flash and
the buzzer sounds during operation, stop the machine immediately and investigate the cause.
For details, see "TROUBLESHOOTING (PAGE 3-140)".
When loading, be careful to load the dump body uniformly, and be particularly careful to avoid loading too much
at the front.
On slippery road surfaces, apply the retarder control lever slowly and shift the transmission down to prevent the
rear wheels from locking.

PERMISSIBLE WATER DEPTH

If there is no way to avoid running the dump truck in the water
during the operation, make sure that it does not go deeper than the
allowable depth (i.e. up to the inner surface of rim (1).
Moreover, flush the dump truck with fresh water after the work and
apply grease to the portions soaked in water.

While the dump truck was running in the water, water may have
seeped into the drain tank. In that case, drain the water
accumulated in the tank in reference to "RECOVER OIL LEAKING
FROM FLOATING SEAL (PAGE 4-82)".

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OPERATION

PARKING MACHINE

WARNING

Avoid stopping suddenly. Give yourself ample room when stopping.
Park the machine on firm, horizontal ground.
Do not park the machine on a slope.
If it is unavoidably necessary to park the machine on a slope, put blocks
under the tires to prevent the machine from moving.
If the shift lever is touched by mistake, the machine may move
suddenly, and this may lead to a serious injury or death. Before
standing up from the operator's seat, always set the parking brake
switch securely to the PARKING position.
The retarder must not be used as a parking brake.
Do not use the retarder for long-term parking, regardless of the engine
speed.

CAUTION

To prevent damage to the parking brake, apply the parking brake only when
parking the machine.

1. Release accelerator pedal (1), then depress brake pedal (2) to

stop the machine.

2. Move shift lever (3) to the N position, then set parking brake

switch (4) to the PARKING position to apply the parking brake.

3. When in the operator's compartment, pull retarder control lever

(5) fully to apply the retarder.

NOTICE

The retarder must not be used as a parking brake.
Do not use the retarder for long-term parking, regardless of the engine
speed.

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OPERATION

HANDLING TIRES

PRECAUTIONS WHEN HANDLING TIRES

WARNING

To ensure safety, the defective tires given below must be replaced with
new tires.

Tires where the bead wire has been cut, broken, or greatly deformed
Excessively worn tires where more than 1/4 of the circumference of the
carcass ply (excluding the breaker) is exposed
Tires where damage to the carcass exceeds 1/3 of the tire width
Tires where ply separation has occurred
Tires where radial cracks extend to the carcass
Tires where there is abnormal deterioration, deformation, and damage,
and the tire cannot withstand use.

Please contact your Komatsu distributor when replacing the tires.
It is dangerous to jack up the machine without taking due care.

T.Km.P.H (Ton-Km-Per-Hour Rating)

Tires for construction equipment are used under severe conditions that bear no comparison with the tires used on
cars, buses, or ordinary trucks, so they are specially designed to withstand these conditions.

Compared with ordinary tires, far greater heat is produced in the rubber internal parts of off-road tires when the
machine is traveling. If they are used continuously under conditions which exceed the permitted load and travel
speed of the tire, the internal temperature will exceed the limit, and the rubber may become soft and heat separation
occur.

To prevent such problems from occurring, the T.Km.P.H. is used as a standard to allow the machine to travel safely.
If operations are carried out which exceed the T.Km.P.H. of the tire (when the T.Km.P.H. of the work exceeds the
T.Km.P.H. of the tires), tire trouble will occur more frequently. In such cases, do as follows.

Make the operating conditions easier so that the operation T.Km.P.H. of the work is lowered.
Increase the size of the tires to a tire with a high T.Km.P.H.

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OPERATION

TIRE T.Km.P.H.AND MAXIMUM SPEED FOR CONTINUOUS TRAVEL (REFERENCE)

Tire T.Km.P.H.for

ambient temperature

Max.speed for continuous travel

for ambient temperature (km/h)

Size 27.00R49

(standard)
structure GP
Code No. E4
(TRA)

625

569

513

456

When empty

(front wheel standard)

When loaded

(rear wheel standard)

Size 31/90R49

(if equipped)
structure GP
Code No. E4
(TRA)

632

580

528

475

When empty

(front wheel standard)

When loaded

(rear wheel standard)

METHOD OF CALCULATING WORK T.Km.P.H.

Work T.Km.P.H. = average load per tire x average travel speed for one day
Average travel speed = round trip distance x number of round trips per day/total operating hours per day
Average load = (load when empty + load when loaded) /2

The total operating hours per day includes the stopping time and rest periods.

* The T.Km.P.H. in the table may differ slightly according to the tire maker, so concerning operations which require

travel near the travel speed given in the table, consult your Komatsu distributor.

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OPERATION

PRECAUTIONS FOR LONG DISTANCE TRAVEL

WARNING

Always maintain the tire inflation pressure at the specified value. If the tire is not at the proper inflation pressure, the rim will be
damaged. If the rim is damaged, there is danger that the ring may fly off when the tire is inflated and cause serious personal injury.

If the machine travels continuously at high speed for a long distance, there will be a marked increase in the
generation of heat in the tire. This may cause premature damage to the tire, so be careful of the following points.

Travel only when empty.
Check the tire inflation pressure before starting for the day when the tires are cold, and adjust to the following
inflation pressure.
Do not reduce the tire inflation pressure when traveling.

Tire size

Inflation pressure

27.00R49

(standard)

0.69MPa {7.00kgf/cm

, 99.4PSI}

31/90R49

(if equipped)

0.69MPa {7.00kgf/cm

, 99.4PSI}

NOTICE
If the tires are used when the inflation pressure is less than the value given in the table above, the rim may be damaged.
Always keep the tire inflation pressure within +0 to +0.03 MPa {0.3 kgf/cm

, 4.3 PSI} of the value in the table above.

The maximum travel speed must be kept to less than 40 km/h (24.9 MPH). Stop for at least one hour for every
one hour of travel to allow the tires and other components to cool down.
Never travel with water or dry ballast in the tires.

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OPERATION

DETERMINING AND MAINTAINING TRAVEL ROAD

Determining and traveling the road in the jobsite is an extremely important factor both for reasons of safety and for
reducing the cycle time.To ensure safety in operations, do as follows.

DETERMINING TRAVEL ROAD

As far as possible, restrict the travel road to one-way travel.
If it is impossible to keep to one-way traffic, make the road with ample width to enable trucks traveling in opposite
directions to pass each other. If it is impossible to provide a sufficient road width, provide passing places at
various points along the road.
Always design the road so that the loaded truck passes on the side closest to the hill face.
If there are curves with poor visibility along the road, set up mirrors.
In places where the road shoulder is weak or likely to collapse, set up a sign at a point at least 1.5 m (4 ft 11 in)
from the road shoulder to warn of the danger.
It is important to set up lighting or reflectors to enable the road to be traveled at night.
The grade of slope should be kept within 10% (approx. 6

) as far as possible, and emergency escape points

should be set up on downhill slopes in case of any brake failure.
Make the road as straight as possible, and particularly in intermediate areas with curves, where the machine is
traveling at high speed, make the radius of the curve as large as possible.
Small S curves are particularly dangerous, so avoid such curves. The radius of the curve must be a minimum of
12 to 15 m (39 ft 4 in to 49 ft 3 in).
Make the radius of curves as large as possible.
Make the road wider at curves than it is in straight areas.
Make the outside of the curve slightly higher.
Be particularly careful to strengthen the road shoulder on the outside of curve.
As far as possible, design the road so that no other roads cross it. In particular, if roads cross at an angle on
slopes, a stepped difference is formed in the road. This is extremely dangerous, as it causes the machine to roll
when traveling at high speed.
Cut the slope face to provide a special road for the trucks.

MAINTAINING TRAVEL ROAD

Carry out the necessary action according to the conditions to insure that the road can always be traveled safely.

Remove any unevenness in the travel surface, sloping to the left or right, or drooping of the road shoulder. Make
the road of ample strength and remove such obstacles as rocks and tree stumps.
Maintain the road from time to time with a bulldozer or motor grader.
Spray the road with water at suitable intervals to prevent dust from rising and reducing the visibility.

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OPERATION

TRANSPORTATION

PRECAUTIONS WHEN TRANSPORTING

Always obey the traffic regulations when transporting the machine by road.

WARNING

This machine must be disassembled for transportation. When transporting the machine, please consult your Komatsu
distributor.

STEPS FOR TRANSPORTATION

As a basic rule, always transport the machine on a trailer.
When selecting the trailer, see the weights and dimensions given in "SPECIFICATIONS (PAGE 5-2)".
Note that the specifications for the weights and dimensions for transportation differ according to the type of tires and
type of dump body.

METHOD OF SECURING MACHINE

After loading the machine in the specified position, secure it in place as follows.

1. Set the parking brake switch to the PARKING position to apply

the parking brake.

2. Turn the key in the starting switch to the OFF position to stop

the engine.

3. Remove the key from the starting switch.

4. To prevent the machine from moving during transportation,

insert blocks under the front and rear of each tire and secure
the machine firmly in position with chains or wire rope.
Be particularly careful to secure the machine firmly so that it
does not slide to the side.

NOTICE
Always retract the antenna and reassemble the mirrors so that they are
within the width of the machine.

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OPERATION

TRANSPORTATION

METHOD OF LIFTING MACHINE

When lifting the machine at a port or any other place, always use the following procedure to lift it.

WARNING

The operator carrying out the lifting operation using a crane must be a properly qualified crane operator.
Never raise the machine with any worker on it.
Always make sure that the wire rope is of ample strength for the weight of this machine.
When lifting, keep the machine horizontal.
Always stop the engine and apply the brake before starting the lifting operation.
Never enter the area around or under the machine when it is raised.

Never try to lift the machine in any posture other than the posture given in the procedure below or using lifting
equipment other than in the procedure below.
There is a hazard that the machine may lose its balance.

NOTICE
This method of lifting applies to the standard specification machine.
The method of lifting differs according to the attachments and options installed.
For details of the procedure for machines that are not the standard specification, please consult your Komatsu distributor.

For the weight of the standard specification machine, see "WEIGHT TABLE (PAGE 3-134)".

NOTICE

Use protectors to prevent the wire rope from being cut on sharp corners and to prevent the wire rope from cutting into the
machine bodywork.
When using a spreader bar, select an ample width to prevent contact with the machine.

Please consult your Komatsu distributor before carrying out lifting work.

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OPERATION

TRANSPORTATION

LOCATION OF LIFTING POSITION MARK

WEIGHT TABLE

Machine weight Front wheel load Rear wheel load

Center of gravity

(from front axle)

HD785-7

72000 kg

(158760 lb)

33840 kg

(74617 lb)

38160 kg

(84143 lb)

2623 mm

(8 ft 7 in)

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OPERATION

TRANSPORTATION

LIFTING PROCEDURE

Lifting work can be carried out only with machines displaying a lifting mark.
When carrying out the lifting operation, stop the machine on firm level ground, and do as follows.

1. Start the engine, set the dump lever to the FLOAT position, and

check that the body pilot lamp goes out.

2. Stop the engine, apply the brake, and check that the area

around the operator's compartment is safe.

3. Select wire ropes, slings, spreader bars and other lifting

equipment to match the weight of the machine, and fit the wire
ropes to the lifting positions.

REMARK

The lifting positions for the machine differs according to the
conditions.
Machine with body:Positions (1) and (3)

Total:4 places (2 at front, 2 at rear)

Machine without body:Positions (1) and (2)

Total:4 places (2 at front, 2 at rear)

4. Fit protector blocks at the contact points between the lifting equipment and the body to prevent damage to the

King equipment.

5. When the machine comes off the ground (raised 10 to 20 cm(3.9 to 7.9 in)), stop the lifting operation, check

carefully that the machine is balanced and that the wire ropes are not loose, then continue the lifting operation
slowly.

3 - 135

OPERATION

COLD WEATHER OPERATION

PRECAUTIONS FOR LOW TEMPERATURE

If the temperature becomes low, it becomes difficult to start the engine, and the coolant may freeze, so do as follows.

FUEL AND LUBRICANTS

Change to fuel and oil with low viscosity for all components. For details of the specified visicosity, see
"RECOMMENDED FUEL, COOLANT, AND LUBRICANT (PAGE 4-11)".

COOLANT

WARNING

Antifreeze is toxic. Be careful not to get it into your eyes or on your skin. If it should get into your eyes or on your skin, wash
it off with large amounts of fresh water and see a doctor at once.
When changing the coolant or when handling coolant containing antifreeze that has been drained when repairing the radiator,
please contact your Komatsu distributor or request a specialist company to carry out the operation. Antifreeze is toxic. Do not
let it flow into drainage ditches or spray it onto the ground surface.
Antifreeze is flammable. Do not bring any flame close. Do not smoke when handling antifreeze.

NOTICE

If it is available, always use Komatsu super coolant (AF-NAC). If it is not available, use permanent type coolant.
Never use methanol, ethanol, or propanol-based antifreeze.
Never use any water leak prevention agent, either alone or in combination with antifreeze.
Do not mix different brands of antifreeze.

For details on the amount of antifreeze mixture and on when to change the coolant, see "CLEAN INSIDE OF
COOLING SYSTEM (PAGE 4-32)".

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OPERATION

COLD WEATHER OPERATION

BATTERY

WARNING

The battery generates flammable gas. Do not bring fire or sparks near the battery.
Battery electrolyte is dangerous. If it gets in your eyes or on your skin, wash it off with a large amount of water and consult a
doctor.
Battery electrolyte dissolves paint. If it gets on the bodywork, wash it off immediately with water.
If the battery electrolyte is frozen, do not charge the battery or start the engine with a different power source. There is danger
that the battery may explode.
Battery electrolyte is toxic. Do not let it flow into drainage ditches or spray it on to the ground surface.

When the ambient temperature drops, the capacity of the battery will also drop. If the battery charge ratio is low, the
battery electrolyte may freeze. Maintain the battery charge as close as possible to 100%. Insulate it against cold
temperature to ensure the machine can be started easily the next morning.
Measure the specific gravity and calculate the rate of charge from the following conversion table.

Electrolyte

Temperature

(

Charging
Rate (%)

-10

-20

100

1.28

1.29

1.30

1.31

1.26

1.27

1.28

1.29

1.24

1.25

1.26

1.27

1.23

1.24

1.25

1.26

When adding distilled water in cold weather, add it before starting operations in the morning to prevent the
electrolyte from freezing.

INSTALLATION OF RADIATOR CURTAIN

(If equipped)
If the display for the engine water temperature gauge does not enter the white range, install a radiator curtain.
It is possible to adjust the degree of opening of the radiator curtain (fully closed, one side open, and both sides open).
Adjust to a suitable condition to match the ambient temperature so that the engine water temperature gauge display
enters the white range.

PRECAUTIONS AFTER COMPLETION OF WORK

To prevent mud, water, or the undercarriage from freezing and making it impossible for the machine to move on the
following morning, observe the following precautions.

Mud and water on the machine body should be completely removed. This is to prevent damage to the seal caused
by water in mud or dirt getting inside the seal and freezing.
Park the machine on hard, dry ground.
If this is impossible, park the machine on wooden boards.
The boards help protect the tracks from being frozen in soil and the machine can start next morning.
Open the drain valve and drain any water collected in the fuel system to prevent it from freezing.
As the battery capacity drops markedly in low temperatures, cover the battery or remove it from the machine,
keep it in a warm place, and install it again the next morning.
If the electrolyte level is low, add distilled water in the morning before beginning work. Do not add water after the
day's work to prevent diluted electrolyte in the battery from freezing during the night.

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OPERATION

LONG-TERM STORAGE

BEFORE STORAGE

When keeping in long-term storage (more than one month), store as follows.

After every part is washed and dried, house the machine in a dry building. Never leave it outdoors.
In case it is indispensable to leave it outdoors, park the machine on the flat ground and cover it with canvas etc.
Fill the fuel tank. This will prevent rust from forming inside the tank.
Lubricate and change the oil before storage.
Coat the exposed portion of the hydraulic cylinder piston rod with grease.
Disconnect the negative terminals of the battery and cover it or remove it from the machine and store it separately.
Apply the parking brake.
Set the tire inflation pressure for each tire to within the range of the specified inflation pressure for the type of tire.
Push the retarder control lever forward to the OFF position.
Place the gear shift lever at the N position and turn the starting switch OFF.
To prevent corrosion, be sure to fill the cooling system with Supercoolant (AF-NAC) or permanent type antifreeze
(density between 30% and 68%).

DURING STORAGE

WARNING

If it is necessary to perform the rust-prevention operation while the machine is indoors, open the doors and windows to improve
ventilation and prevent gas poisoning.

Operate the engine and move the machine for a short distance once a month so that a new film of oil will be coated
over movable parts and component surfaces. At the same time, also charge the battery.
Before operating the work equipment, wipe off all the grease from hydraulic piston rods.

AFTER STORAGE

NOTICE
If the machine has been stored without carrying out the monthly rust-prevention operation, consult your Komatsu distributor
before using it.

When using the machine after long-term storage, do as follows before using it.

Wipe off the grease from the hydraulic cylinder rods.
Add oil and grease at all lubrication points.
When the machine is stored for a long period, moisture in the air will mix with the oil. Check the oil before and after
starting the engine. If there is water in the oil, change all the oil.

PRECAUTIONS BEFORE TRAVELING AFTER LONG-TERM STORAGE

1. Check all the oil and water levels before traveling.
2. When traveling after long-term storage, travel forward at a speed of 10 to 15 km/h (6.2 to 9.3 MPH) for 5 minutes

or 1 km to run the machine in, then change to normal travel.

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OPERATION

TROUBLESHOOTING

AFTER RUNNING OUT OF FUEL

If you have run out of fuel, add fuel to the fuel tank and bleed air from the fuel system and then start the engine.

PROCEDURE FOR BLEEDING AIR

CAUTION

The fuel injection pump and nozzle of this engine consist of more precise parts than the conventional ones.  If foreign matter
enters them, it can cause a trouble.  Accordingly, if dust sticks to the fuel system, wash it off with clean fuel.
When opening the air bleeding plug at the fuel filter head, take care.  Fuel may spout because of residual pressure.

Use the same procedure on the left and right to bleed the air from the fuel system.

1. Fill the fuel tank with fuel.
2. Remove the wing nut from cover (1).

3. Loosen air bleeding plug (2) at the fuel main filter head.
4. Loosen wing nut (4) holding lever (5) of priming pump (3) in

position. Pump lever (5) and make fuel overflow until no more
bubbles come out with the fuel from air bleed plug (2).

5. Tighten air bleed plug (2).

Tightening torque for air bleed plug
7.8 to 9.8 N

m{0.8 to 1 kg

m, 5.8 to 7.2 lbft}

6. Loosen air breather (6) at the side of the supply pump.
7. Pump lever (5) and make fuel overflow until no more bubbles

come out with the fuel from air breather (6).

8. Tighten air breather (6), then tighten wing nut (4) of priming

pump (3) securely to lock lever (5) in position.

Tightening torque for air breather:
4.9 to 6.9 N

m {0.5 to 0.7 kg

m, 3.6 to 5.1 lbft}

Tightening torque for wing screw
6.9 to 12.7 N

m {0.7 to 1.3 kg

m, 5.1 to 9.4 lbft}

9. Turn the key in the starting switch to the START position and start the engine.

When doing this, do not crank the starting motor continuously for more than 20 seconds. If the engine does not
start, wait for at least 2 minutes, then try again. Perform this operation a maximum of 4 times.

10. If the engine does not start, repeat the procedure from Step 2.

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OPERATION

TROUBLESHOOTING

IF TRANSMISSION HAS TROUBLE

If the transmission has any trouble, operate the machine according to the following procedure.

1. Decelerate the machine with the brake and stop it on a safe place.
2. Set the shift lever to the N position, then set the parking brake switch to the PARKING position.
3. In some trouble modes, the gear is not shifted even if the shift lever is operated.

In this case, perform the following procedure.

1) Remove emergency escape connector (1) (No. A-1F, A-M,

white 1-pin connector), then insert it again.

2) Set the parking brake switch to the TRAVEL position.
3) Operate the shift lever to move the machine to a safe place

without depressing the accelerator pedal.

If the gear shift lever is operated with the accelerator pedal depressed, the emergency escape function will not work.
In addition, the emergency escape function may not work for some failure codes.

While the emergency escape function is working, the shift indicator of the machine monitor displays "E" and the shift
range (gear speed) of the transmission alternately.

METHOD OF LOWERING DUMP BODY IN EMERGENCY

When the dump body needs to be lowered to the seat while the engine cannot be started for some trouble, perform
the following procedure.

1. Remove hydraulic tank cap (F) and release the remaining

pressure in the hoist circuit.

2. Loosen locknut (2) of manual lower valve (1).
3. Turn grip (3) of valve (1) counterclockwise.

The oil in the hoist cylinder is drained into the hydraulic tank
and the dump body lowers.

4. Tighten grip (3) and locknut (2).

If the dump body does not go down even when the above
method is used, please consult your Komatsu distributor.

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OPERATION

TROUBLESHOOTING

METHOD OF TOWING MACHINE

WARNING

Injury or death could result if a disabled machine is towed incorrectly or if
there is a mistake in the selection of the wire rope or drawbar.

Always confirm that the wire rope or drawbar used for towing has ample
strength for the weight of the machine being towed.
Never use a wire rope which has cut strands (A), reduced diameter (B),
or kinks (C). There is danger that the rope may break during the towing
operation.
Always wear leather gloves when handling wire rope.
Never tow a machine on a slope.
Never go between the towing machine and the towed machine during
the towing operation.
If the machine moves suddenly, a load is applied suddenly to the towing
wire rope or drawbar, and the towing wire or drawbar may break. Move
the machine gradually to a constant speed.
Be extremely careful if there is a failure in the engine or brake system:
the brakes will not work.
If the steering and the brakes on the disabled machine cannot be
operated, do not let anyone ride on the disabled machine.

NOTICE

The permissible towing capacity for this machine is 532305N (54280kg). Do not tow any load greater than this.
Towing is only permitted in order to move a disabled machine to a place where it is possible to carry out inspection and
maintenance. It must not be towed for long distances.
Please consult your Komatsu distributor for information about towing a disabled machine.

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OPERATION

TROUBLESHOOTING

This machine must not be towed except in emergencies. When towing the machine, take the following precautions.

When towing a machine, tow it at a low speed of less than 2 km/h (1.2 MPH), and for a distance of a few meters
to a place where repairs can be carried out.  The machine should be towed only in emergencies.  If the machine
must be moved long distances, use a transporter.
Use a towing machine of the same class as the machine being towed.
Check that the towing machine has ample braking power, weight, and rimpull to allow it to control both machines
on slopes or on the tow road.
Use the specified hook for both the towing machine and the machine being towed.
To protect the operator if the towing wire or towing bar breaks, install protective plates on both the towing machine
and the machine being towed.
There are towing hooks under the front frame and under the rear axle.  Do not use any other part for the towing
hook.
When fitting the towing wire, check the condition of the hook to make sure that there is no problem.
Keep the angle of the towing wire as small as possible.
Keep the angle between the center lines of the two machines to within 30 degrees.
Towing may be carried out under various differing conditions, so it is impossible to determine beforehand the
requirements for towing.
Towing on flat horizontal roads will require the minimum rimpull, while towing on slopes or on uneven road
surfaces will require the maximum rimpull.
If the pressure in a hydraulic circuit has dropped because of leakage of oil, the parking brake will be applied, so
release the parking brake before towing.
Before releasing the parking brake, always put blocks under all four wheels.  If the wheels are not blocked, there
is danger that the machine may move.
Connect with the towing wire or drawbar, and remove the blocks from the wheels when the disabled machine is
in a condition where it cannot run away.
When releasing the parking brake, check first that the surrounding area is safe.
When the parking brake is released, the brakes cannot be used, so check carefully that the situation is safe.
When towing down a slope, use two towing machines.  One machine should be uphill from the disabled machine
and should be connected with towing wire or a drawbar to pull the disabled machine back and keep it stable.  The
other machine should tow the disabled machine downhill.

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OPERATION

TROUBLESHOOTING

WHEN ENGINE RUNS

If the transmission and steering wheel can be operated, and the engine is running, it is possible to tow the
machine out of mud or to move it for a short distance to the edge of the road.
Check the effect of the brakes, and if the brakes do not work properly, take the action given in "When engine does
not run".
Check if it is possible to steer the machine. If the machine cannot be steered, follow the procedure given in
"WHEN ENGINE DOES NOT RUN".
The operator should sit on the machine being towed and operate the steering in the direction that the machine
is towed.
Always run the engine to allow the steering and brakes to be used.

WHEN ENGINE DOES NOT RUN

The brakes will not work, so be extremely careful.
Connect the towing machine securely to the towed machine. Use two towing machines of the same class or
larger than the machine being towed: connect one machine each to the front and rear of the machine being towed.
If it is necessary to change the direction of the machine being towed, it is possible to use the emergency steering,
but it can be used for a maximum of only 90 seconds.
If the emergency steering cannot be used, disconnect two hydraulic hoses each on the left and right from the
steering cylinders, then carry out the towing operation. When removing the hoses, block the hoses with plugs and
fit oil containers to the mouthpiece of the cylinder to prevent oil from draining to the ground.

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OPERATION

TROUBLESHOOTING

WHEN PARKING BRAKE HAS BEEN ACTUATED IN EMERGENCY

If the pressure in the hydraulic circuit goes down abnormally because of oil leakage or some other cause, the parking
brake is automatically applied.
It is necessary to tow or move the machine, the parking brake must be released. Release the parking brake as
follows.

METHOD OF RELEASING PARKING BRAKE IN EMERGENCY

Please ask your Komatsu distributor to release the parking brake.

WARNING

If any abnormality occurs in the hydraulic circuit, there is danger that the wheel brakes may not be applied properly, so always
travel at low speed when towing the machine.
When carrying out the operation to release the parking brake, check that the surrounding area is safe, and always put blocks
under all four wheels before starting the operation. If the wheels are not blocked, there is danger that the machine may
suddenly move.
Always stop the engine before starting the operation to release the parking brake.

1. When releasing the parking brake manually, prepare 34 M16 (80-95 mm (3.2 - 3.7 in) below head, pitch 2.0 mm

(0.079 in) (flat)) bolts and M16 washers each.

2. Prepare a container to catch the oil.
3. Stop the engine.
4. Put blocks under the wheels.
5. Set the container to catch the oil under the brake portion.
6. Remove plug (1) from the rear axle brake portion.

REMARK

There are 9 plugs on the right side and 9 plugs on the left side.

7. Remove plug (2) from the front axle brake portion.

REMARK

There are 8 plugs on the right side and 8 plugs on the left side.

8. Pass the brake release bolt through the washer and insert it

into the plug hole.

NOTICE
If the bolts are not tightened uniformly, the internal piston will be distorted or damaged. Tighten the bolts in turn on diagonally
opposite sides.

9. Tighten the brake release bolts uniformly. (Both left and right front and rear wheels)

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Galeo HD785-7 DUMP TRUCK. Operation and Maintenance Manual (2006) - page 6