Hydraulic System; General - jcb JS300 Service Manual

General

Discharge
1. Make the machine safe.
Refer to: Maintenance > Maintenance Positions > Maintenance Position (Excavator Arm Lowered)
(Page 184).
2. Turn the ignition key to the on position.
3. Lower the controls isolation lever and push the controls isolation switch.
Refer to: Operation > Locks > Control Lock (Page 59).
4. Operate the hand controllers in all directions to release the pressure from the hydraulic system.
Refer to: Operation > Operating Levers/Pedals > Excavator Arm Controls (Page 96).
5. Turn the ignition key to the off position.
6. Remove the ignition key.
7. Push the rubber boot on the hydraulic tank breather to release the pressure from the tank.
Refer to: Maintenance > Service Points (Page 185).
Check (Condition)
Hydraulic Hoses
WARNING Damaged hoses can cause fatal accidents. Examine the hoses regularly. Do not use the machine
if a hose or hose fixture is damaged.
Examine the hoses for:
• Damaged hose ends
• Worn outer covers
• Ballooned outer covers
• Kinked or crushed hoses
• Embedded armouring in the outer covers
• Displaced hose end fittings.
Replace a damaged hose before you use the machine again.
The replacement hoses must be of the same size and standard. If necessary, for more information contact
your JCB dealer.
Accumulator
1. Stop the machine on solid, level ground.
2. Raise the boom and extend the dipper.
Refer to: Operation > Operating Levers/Pedals (Page 96).
3. Stop the engine. Do not raise the controls isolation lever.
Refer to: Operation > Locks (Page 59).
4. Lower the boom. Stop the boom several metres from the ground.
5. Lower the boom to the ground.
There must be sufficient pressure stored in the accumulator to lower the boom to the ground in two stages. If
this is not possible, contact your JCB dealer.
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Hydraulic System

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Maintenance
Hydraulic System
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