Komatsu Hydraulic Excavator PC450LC-6

WARNING: The oil is at high temperature immediately after the machine has been operated. Wait for the oil to cool down before carrying out maintenance.

Container to catch drained oil: Min. 21.5 ℓ capacity

Refill capacity: 21.5 ℓ (5.7 US gal, 4.7 UK gal)

Set a container under drain valve Ⓔ under the machine body to catch the oil

Loosen drain valve Ⓔ under the machine body, drain the oil, then tighten the drain plug again

Remove dipstick Ⓖ and air bleed plug ①, then add the specified amount of engine oil through filler port Ⓕ of the dipstick guide

NOTICE: For details of the oil to use, see “20. USE OF FUEL, COOLANT AND LUBRICANTS ACCORDING TO AMBIENT TEMPERATURE”

After adding oil, install air bleed plug ①

Wipe off the oil on the dipstick with a cloth

Warning: This procedure requires trained personnel with PPE!

Loosen nuts and bolts ①, ②, and ③

Turn nut ④ clockwise and move alternator ⑤ so that the deflection of the belt is approx. 10 mm (at approx. 6 kg (13 lb))

Tighten nuts and bolts ①, ②, and ③ to secure alternator ⑤ in position

Enter the tightening torque for lock nuts ①, ②

Enter the tightening torque for bolts ③

Enter the tightening torque for bolts ④

Check each pulley for breakage, wear of the groove, and wear of the belt

Check in particular that the belt does not contact the bottom of the groove

WARNING: Engine is at high temperature immediately after the machine has been operated. Wait for engine to cool down before replacing the filter. Do not bring fire or sparks near the fuel.

Prepare a filter wrench and a container to catch the fuel.

Set the container to catch the fuel under the filter cartridge.

Using a filter wrench, turn filter cartridge ① counterclockwise to remove it.

Clean the filter holder, fill a new filter cartridge with clean fuel, coat the packing surface with engine oil, then install it to the filter holder.

When installing, tighten until the packing surface contacts the seal surface of the filter holder, then tighten it up 1/2 to 3/4 of a turn.

If the filter cartridge is tightened too far, the packing will be damaged and this will lead to leakage of fuel. If the filter cartridge is too loose, fuel will also leak from the packing, so always tighten to the correct amount.

After replacing the fuel filter cartridge, bleed the air from the system.

Fill the fuel tank with fuel (to the position where the float is at the maximum position).

Do not open the radiator cap unless necessary

When checking the coolant, always check the radiator reserve tank when the engine is cold

1. Open the right rear cover on the machine and check that the cooling water level is between the FULL and LOW marks on radiator reserve tank (①) (shown in the diagram on the right)

If the water level is low, add water through the water filler of reserve tank (①) to the FULL level

2. After adding water, tighten the caps securely

3. If the reserve tank becomes empty, first inspect for water leaks and then fill the radiator and the reserve tank with water;

WARNING: If fuses are frequently blown or if there are traces of short circuit on the electrical wiring, locate the cause and carry out repair

Accumulation of flammable material (dead leaves, twigs, grass, etc.) around the battery may cause fire, so always check and remove such material

Keep the top surface of the battery clean and check the breather hole in the battery cap

If it is clogged with dirt or dust, wash the battery cap to clean the breather hole

Check for damage and wrong capacity of the fuse and any sign of disconnection or short circuit on the electric wiring

Check also for loose terminals and tighten any loose parts

Check the wiring of the “battery”, “starting motor” and “alternator” carefully in particular

When carrying out walk-around checks or checks before starting, always check if there is any accumulation of flammable material around the battery, and remove such flammable material

Please contact your Komatsu distributor for investigation and correction of the cause