46
13 Maintenance and servicing
The resulting symptoms in hydrostatic systems can be:
P
Noisy operation.
P
Lack of power or drive after short-term operation.
P
High operating temperature and excessive oil expansion.
Before starting, make sure that the oil level in the gearbox is correct.
The following procedures are best carried out with the vehicle wheels on
the ground. Then repeat under normal operating conditions. If this is not
possible, the procedure should be carried out in an open area free of objects
or bystanders.
P
Switch off the brake if it is activated.
P
With the bypass valve open and the engine running, slowly move the
direction controller in the forward and reverse direction (5 to 6 times).
P
With the bypass valve closed and the engine running, slowly move the
direction control forward and backward (5 to 6 times). Check the oil level
and top up oil after switching off the engine.
It may be necessary to repeat the steps until all air is completely removed from
the system. When the gearbox operates at normal noise level and moves
smoothly forward and backward at normal speeds, the gearbox is considered
cleaned.