Bleeding Air From Hydraulic System - Komatsu PC18MR-3 Operation & Maintenance Manual

MAINTENANCE

BLEEDING AIR FROM HYDRAULIC SYSTEM

1. Start the engine. For details, see "STARTING ENGINE (PAGE 3-44)".
Run the engine at low idle for 10 minutes, then do as follows.
2. Bleeding air from cylinders
NOTICE
If the engine is run at high speed immediately after startup or a cylinder is pushed up to its stroke end, air taken inside the cylinder
may cause damage to the piston packing.
1) Run the engine at low idle, and extend and retract each cylinder 4 to 5 times, taking care that a cylinder is
not moved to the end of its stroke. (Stop the cylinder approx. 100 mm (3.9 in) short of its stroke end)
2) Next, operate each cylinder 3 to 4 times to the end of its stroke.
3) Finally, operate each cylinder 4 to 5 times to the end of its stroke to completely remove the air.
3. Bleeding air from attachment (when installed)
NOTICE
If the method of bleeding the air from the attachment itself is specified by the manufacturer, bleed the air according to the
specified procedure.
After completing the air bleeding operation, stop the engine, and leave the machine for 5 minutes before starting operations.
This will remove the air bubbles in the oil inside the hydraulic cylinders.
Check that there is no leakage of oil and wipe off any oil that has been spilled.
If a breaker or other attachment has been installed, run the engine at low idle and operate the attachment pedal
repeatedly (approx. 10 times) until the air has been bled from the attachment circuit.
MAINTENANCE PROCEDURE
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