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INFORMATION!
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Follow these rules when jacking up the trailer wheel:
- couple the trailer with the tractor, move to level ground and
engage the tractor parking brake;
- chock the wheel that is not being jacked up;
- place the jack under the axis and near the jacked up wheel, and
lift the wheel so that it clears the ground;
- secure the wheel from falling by putting a prop of suitable
height under the axis.
7.2. Brakes
7.2.1. Brakes – servicing the brake pneumatic system
When servicing the trailer, check the tightness and the condition of parts and connections of
the braking system, and periodically drain the water condensate from the air tank.
Check the leak tightness of the system at the rated pressure of approx. 800 kPa for the two-
line system. Leaks are detected by a distinct hiss or air bubbles (after coating with soap water)
at the points of air escape from the system. If the leaks are caused by damaged seals, lines or
other parts (valves, actuators, etc.), replace them with new parts.
Drain the water from the air tank by tilting the drain valve stem to the side when the tank is
pressurised; the drain valve must also be unscrewed from the tank and cleaned of accumulated
dirt once a year, before the winter season.
7.2.2. Brakes – servicing the brake hydraulic system
When servicing the trailer, check the tightness and the condition of parts and connections
of the braking system.
Check the leak-tightness of the system at the rated pressure of approx. 140 bar. Test the
leak-tightness of the system by actuating the hydraulic cylinders to fully extend and hold them
for approximately 30 seconds. Leaks are detected by the oil that escapes from the system;
if found at line connections, retighten the connections and repeat the test. If the leaks are caused
by damaged seals, lines or other parts (valves, actuators, etc.), replace them with new parts.
Proceed with a similar test when charging the hydraulic accumulator: press down and hold the
brake pedal for approximately 5 seconds.
7.2.3. Brakes – adjustment of the braking system components
When servicing the trailer, check the condition of parts and connections of the braking
system, and periodically inspect the lubrication of control elements.
Adjust the brakes when the following occurs:
- there is excessive clearance between the shoes and the drum from the brake shoe wear,
resulting in decreased braking performance;
