KOMATSU H285S HYDRAULIC SHOVEL Operation & Maintenance Manual (SN:78067) KOMATSU H285S – PDF

Page 140

Assembly process No.

Bleeding air from hydraulic cylinders

A-21

a After disassembling for transportation, changing the oil in the hydraulic tank, or removing the hydraulic cylinders or work equipment piping, bleed the air from the hydraulic circuit as follows. 1. Blade lift cylinder (with piston valve) 1) Start the engine and run at low idling for approx. 5 minutes. 2) With the engine at low idling, extend and retract the cylinder four or five times without operating it to the end of its stroke. a Operate the piston rod to approx. 100 mm form the end of the stroke; do not releive the circuit under any circumstances. 3) Keeping the engine at low idling, retract the cylinder to a point approx. 100 mm before the end of the stroke, then use fine control (at least 10 seconds) to retract the cylinder to the end of its stroke. While operating the lever, hold the cylinder in this position for 3 minutes. 4) With the engine at high idling, retract the cylinder to a point approx. 100 mm before the end of the stroke, then use fine control (at least 10 seconds) to retract the cylinder to the end of its stroke. While operating the lever, hold the cylinder in this position for 1 minute. 2. Blade tilt cylinder (without piston valve) 1) Start the engine and run at low idling for approx. 5 minutes. 2) With the engine at low idling, raise and lower the blade four or five times without operating the cylinder to the end of its stroke. a Operate the piston rod to approx. 100 mm form the end of the stroke; do not relieve the circuit under any circumstances. 3) Repeat this operation with the engine at full throttle, then run the engine at low idling and operate the piston rod to the end of its stroke to relieve the circuit. k If from the beginning the engine is run at full throttle, or the cylinders are operated to the end of

their stroke, the piston packing may be damaged, so never operate in this way. k Check the oil level, and add oil to the specified level if necessary.

Precautions

Necessary tools Name

Other remarks

135

Q'ty

Necessary equipment Name Q'ty


Turn static files into dynamic content formats.

Create a flipbook
Issuu converts static files into: digital portfolios, online yearbooks, online catalogs, digital photo albums and more. Sign up and create your flipbook.
KOMATSU H285S HYDRAULIC SHOVEL Operation & Maintenance Manual (SN:78067) KOMATSU H285S – PDF by www.heydownloads.com - Issuu