Komatsu WA250PT-5H Operation & Maintenance Manual Download

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Outlines of service

MAINTENANCE

Handling oil, fuel, coolant and performing oil clinic

4-4

Outlines of service

Handling oil, fuel, coolant and performing oil clinic

Oil

Oil is used in the engine and work equipment under extremely severe conditions (high temperature, high pres-
sure), and deteriorates with use.
Always use oil that matches the grade and temperature for use given in the Operation and Maintenance Man-
ual.
Even if the oil is not dirty, always change the oil after the specified interval.

Oil corresponds to blood in the human body, so always be careful when handling it to prevent any impurities
(water, metal particles, dirt, etc.) from getting in.
The majority of problems with machines are caused by the entry of such impurities.
Take particular care not to let any impurities get in when storing or adding oil.

Never mix oils of different grades or brands.

Always add the specified amount of oil.
Having too much oil or too little oil are both causes of problems.

If the oil in the work equipment is not clear, there is probably water or air getting into the circuit. In such cases,
please contact your Komatsu distributor.

When changing the oil, always replace the related filters at the same time.

We recommend you have an analysis made of the oil periodically to check the condition of the machine. For
those who wish to use this service, please contact your Komatsu distributor.

Fuel

The fuel pump is a precision instrument, and if fuel containing water or dirt is used, it cannot work properly.

Be extremely careful not to let impurities get in when storing or adding fuel.

Always use the fuel specified in the Operation and Maintenance Manual.
Fuel may congeal depending on the temperature when it is used (particularly in low temperature below -15°C
(5°F)). It is necessary to use the fuel that is suitable for the temperature.

To prevent the moisture in the air from condensing and forming water inside the fuel tank, always fill the fuel
tank after completing the day's work.

Before starting the engine, or when 10 minutes have passed after adding fuel, drain the sediment and water
from the fuel tank.

If the engine runs out of fuel, or if the filters have been replaced, it is necessary to bleed the air from the circuit.

Coolant

River water contains large amount of calcium and other impurities, so if it is used, scale will stick to the engine
and radiator, and this will cause defective heat exchange and overheating.
Do not use water that is not suitable for drinking.

When using antifreeze, always observe the precautions given in the Operation and Maintenance Manual.

This antifreeze is also effective in preventing corrosion on the parts of the engine cooling system. It may be
continuously used for two years or 4000 hours of operation, therefore it may be used throughout the year.

Antifreeze is flammable, so be extremely careful not to expose it to flame or fire.

The proportion of antifreeze to water differs according to the ambient temperature.
For details of the mixing proportions, see “Clean inside of cooling system on page 4-24“.

If the engine overheats, wait for the engine to cool before adding coolant.

If the coolant level is low, it will cause overheating and will also cause problems with corrosion from the air in
the coolant.

Grease

Grease is used to prevent twisting and noise at the joints.

The nipples not included in the maintenance section are nipples for overhaul, so they do not need grease.
If any part becomes stiff after being used for long time, add grease.

Always wipe off all of the old grease that is pushed out when greasing.
Be particularly careful to wipe off the old grease in places where sand or dirt sticking in the grease would cause
wear of the rotating parts.