Komatsu PC18MR-3, Operation & Maintenance Manual

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MAINTENANCE PROCEDURES
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4.9.1.l CHECKING WINDSCREEN WIPER BLADE (machines with cab)
Check only after the windscreen wiper mechanism has been activated. Checking consists in detecting the faulty
cleaning of the wiper carried out with the washer in function. If after cleaning, there are scratches, it means that the
scrapping blade is deteriorated and it is necessary to replace the wiper.
IMPORTANT
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For best functioning of the windscreen wiper mechanism, it is advisable to replace the wiper at least
once a year. Replace it more often if you work in fairly critical environmental conditions. It is also advis-
able to clean the windscreen regularly to remove any dirt, grease or residue of any kind since they can
hamper the wiper regular working.
4.9.1.m BLEEDING THE HYDRAULIC SYSTEM
Start the engine (for details, see paragraph "3.3.1.5 STARTING THE ENGINE") and run it at idle for 10 minutes,
then proceed as indicated below.
Purge the air from the cylinders.
IMPORTANT
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If the engine runs at maximum rpm or if the cylinders are brought to the end of stroke soon after starting,
the air sucked in by the cylinders may damage the piston gaskets.
1. Run the engine at idle, extend and retract each cylinder 4 or 5 times, paying attention so as not to take it to the
end of stroke (stop the cylinders about 100 mm away from the end of stroke).
2. Then, activate each cylinder 3 or 4 times up to the end of stroke.
3. Finally, activate each cylinder 4 or 5 times up to the end of stroke to fully remove the air.
4. Purge the air from the accessories (if fitted).
IMPORTANT
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If the method to purge the air from the accessory is specified by the manufacturer, follow such instruc-
tions.
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After the bleeding operation, stop the engine and wait at least 5 minutes before starting work. This will
eliminate the air bubbles from the oil present inside the hydraulic cylinders.
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Make sure that there are no oil leakages and remove any oil that may have been spilled.
If a demolition hammer or another accessory is installed on the machine, run the engine at idle and press the con-
trol several times (around 10 times), until there is no more air coming from the accessory circuit.