Hydraulic Trailer Brakes - Zetor 8621 Forterra turbo Operator's Manual

OPERATION
F 114

HYDRAULIC TRAILER BRAKES

Hydraulic trailer brake control is synchronized with braking the tractor including the
braking effect. Operating pressure is activated by pressure of oil from hydraulic
pump (1). The hydraulic valve (2) is introduced in the circuit of hydraulic pump. The
hydraulic pump is of gear type (pump can not be disengaged).
The hydraulic trailer brake valve is controlled by the brake fluid pressure activated in
master brake cylinder depending upon the force on brake pedal. The pressure in
brake coupling (4) must be 12 - 15 MPa at maximal press on the brake pedal. Trailer
brake valve prioritizes the function of brake to control of hydraulic. Do not forget to
bleed the trailer brake valve (2) by vent screw (3) when bleeding the service brakes.
In case there are hydraulic shocks in hydraulic circuit if applied service brake pedals
it is necessary to bleed the hose (5) coming from brake valve (2) to quick-coupler
(4).
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