jcb JS300 Service Manual page 130

3.2. Warm up the hydraulic oil by repeatedly selecting bucket crowd by moving the right hand lever to
the left for:
Duration: 5s
3.3. Repeat for several minutes.
3.4. Select dozer up (if installed) by moving the dozer control lever backwards, keep it selected for:
Duration: 1min
4. Warm up the hydraulic circuit.
4.1. Decrease the machine power to medium.
4.2. Raise and lower the boom from ground level to full height, five times.
4.3. Move the dipper fully in both directions, five times.
4.4. Rotate the bucket in both directions fully five times.
4.5. Slew the upper structure clockwise for one revolution and stop.
4.6. Slew the upper structure counterclockwise for one revolution and stop.
4.7. Repeat step 4.3 three times.
5. If the operation still appears slow, then repeat the steps 4.2 and 4.3.
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Operation
Starting the Engine
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