Removal and Installation of Boom Cylinder

Caution ・ Stop the machine on a level location with good footing. ・ Be sure to stop the engine before beginning work. ・ When working together with others, always be sure to exchange signals and pay adequate attention to safety. ・ Always wear protective devices (protective eyewear and safety shoes, etc.) when working with a hammer. ・ Be sure to inspect the nylon sling and other lifting equipment before beginning work. ・ Do not stand or pass under the suspended load.

Items to prepare •Wrenches (19 mm, 30 mm, 36 mm) •Crowbar •Wire rope (with the required lifting capacity) •Crane (with the required lifting capacity) •Marking pen •Caps •Plugs •Hammer •Striking rod •Grease •Rag •Cleaning fluid •Crossties •Wire 1.Removal of Boom Cylinder •When removing only the boom cylinder, put the attachments in the temporary decommissioning posture. •When removing as far as the boom, first remove the bucket, bucket cylinder, arm, and arm cylinder according to their respective removal procedures.

Bring the boom top in contact with the ground. [1] Use a crane and nylon sling (1) to secure the boom cylinder (2).

1 Nylon sling 2 Boom cylinder (right) 2 Boom cylinder (left)

[2] Use a wrench (19 mm) to remove the grease hose (4). •Use caps and plugs to prevent any entry of water, dust or dirt.

[3] Use 2 wrenches (30 mm) to remove the 2 double nuts (5) and bolt (6), and then remove the fastening ring (7).

[4] Use a hammer (8) and striking rod (9) to push the pin (10) out.

[5] Start the engine, lower the boom at idle, and retract the boom cylinder rod.

4 Grease hose 5 Nut 6 Bolt 7 Ring 8 Hammer 9 Striking rod 10 Pin

[6] Tie the cylinder rod with wire (11) so that it cannot come out.

[7] Switch the key switch (12) OFF to stop the engine. Switch the key switch ON again, and then turn the control lever (13) about 10 times to bleed off any pressure.

[8] Move the travel lever (14) back and forth about 5 times to bleed out the pressure.

[9] Switch the key switch OFF.

11 Wire 12 Key switch 13 Control lever 14 Travel lever

[10]Press the air breather button (15) on top of the hydraulic oil tank to release the pressure inside the tank.

[11]Use a wrench (36 mm) to remove the hose (16). •Mark the lines and hoses so that the connectors match at the time of assembly. •Use caps and plugs to cover the hoses and lines to prevent any entry of water, dust or dirt. •Clean the hoses and lines by spraying them with a parts cleaner to prevent scratches and prevent dirt from accumulating on the connectors.

[12]Use a wrench (19 mm) to remove the bolt (17) and washer (18).

15 Air breather button 16 Hose 17 Bolt 18 Washer

[13]Use a crowbar to remove the pin (19).

[14]Use a crane and nylon sling (1) to lift up and remove the boom cylinder (2).

[15]Place the boom cylinder (2) on crossties.

[16]Remove the cab side cylinder (3) with the same procedure.

2.Installation of Boom Cylinder

To install, perform the reverse of the removal procedure. •Clean each pin and pin hole. •When inserting pins, be careful not to damage the dust seals. •As the final step, always grease up.

1 Nylon sling 2 Boom cylinder (left) 3 Boom cylinder (right) 19 Pin