jcb JS300 Service Manual page 187

If impact force is used to do a task, it will cause damage to the dig end. An impact force will also create high
pressures inside the cylinders, which will cause the cylinders to swell.
The cylinders are designed with a cushion mechanism which will gradually release any back pressure. If an
impact force is applied at the end of the cylinder stroke, the piston will hit the head or bottom end and cause
damage.
Stability
A machine which is stable during operation, increases productivity, extends the life of the machine and makes
sure of operator safety.
The dig point effects stability, if the dig point is too far away the machine can become unstable.
Keep the dig point close to the machine to improve stability and increase the dig force.
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Figure 141.
Figure 142.
Figure 143.
Figure 144.
9831/1100-2
Operation
Working with the Excavator Arm
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