330,330 L & 330 LN EXCAVATORS MACHINE SYSTEMS Caterpillar

NOTE: The hydraulic accumulator is installed in the pilot manifold located behind the right rear access door.

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At operating temperature, the hydraulic oil tank is hot and under pressure. Hot oil can cause burns. To prevent possible personal injury, release the pressure in the implement hydraulic circuits (boom, stick and bucket) before any hydraulic lines or components are disconnected or removed.

1. Release the pressure in the hydraulic system as follows:

a. Fully retract the rod in the stick cylinder.

b. Adjust the position of the bucket so it will be flat on the ground when the boom is lowered.

c. Lower the boom until the bucket is flat on the ground.

d. Shut off the engine, and put the hydraulic activation control lever in the "Lock" position.

e. Move the control levers for the boom, bucket, stick and swing through their full travel strokes. This will relieve any pressure that may be present in the pilot system.

f. Slowly loosen the air breather cap on the hydraulic oil tank to release the pressure.

g. Tighten the air breather cap on the hydraulic oil tank.

h. The pressure in the hydraulic system has now been released. Lines and components can now be removed.

NOTE: Do not release the nitrogen from the hydraulic accumulator unless the unit is to be disassembled.

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At operating temperature, the hydraulic oil tank is hot and under pressure. Hot oil can cause burns. To prevent possible personal injury, release the pressure in the implement hydraulic circuits (boom, stick and bucket) before any hydraulic lines or components are disconnected or removed.

2. Remove hydraulic accumulator (1). Remove the O-ring seal from the accumulator.

NOTE: Install the hydraulic accumulator in the reverse order of removal. Prior to installing the accumulator, check the condition of the O-ring seal. If the seal is worn or damaged, use new parts for replacement.

3. Check the oil level in the hydraulic oil tank. Fill the hydraulic oil tank to the correct level. See the Operation & Maintenance Manual for the correct filling procedure.