Driving
5.3 Driving and turning off the truck crane
5 - 44 3 112 993 en Operating manual GMK 6400
12.07.2013
Additional brakes Engine retarder
The truck crane has an engine flap brake which it uses as an engine retarder.
The engine retarder only becomes effective at an engine speed of 900 min
-1
(rpm) and can be used up to a maximum speed of 2300 min
-1
(rpm).
Retarder
The truck crane can also be rigged with a transmission retarder. The braking
force of the transmission retarded depends on the speed. The higher the
speed, the higher the braking power.
Deactivate the retarder function e.g. in icy conditions.
• Press switch (1) below down – the light inside the switch lights up.
Re-activate the retarder function when conditions improve again.
• Press the switch (1) above – the light in the switch goes out.
G
Risk of accident from unexpected acceleration
Maintain sufficient distance when the engine retarder is switched on. The
effectiveness of the engine retarder is interrupted during gear shifting. This
may cause the truck crane to accelerate briefly.
G
Risk of accident in unfavourable road conditions
Deactivate the retarder function when road conditions are unfavourable,
e.g. in icy conditions. This prevents over-braking of the truck crane and pre-
vents it coming off the road.