PRONAR 663/4 SILO, Operator'S Manual, Page: 104 / 135

Pronar T663/4 T663/4 SILO SECTION 5
5.12
Adjustment should be conducted separately for each wheel. Expander arm (1) should be
moved by one notch in chosen direction. If the extent of cylinder action is still incorrect, move
the lever again. After proper brake adjustment, at full braking, the expander arms should
create the angle of 90° with the cylinder piston, and the stroke should amount to
approximately half the length of the total stroke of the piston. After brake release expander
arms may not be supported on any structural elements, because too little withdrawal of a
piston ram may cause abrasion of brake shoes in drum and result in overheating trailer
brakes. Expander arms must be positioned in parallel with regard to each other at full
braking. If this is not so, adjust the position of the lever, which has the longer stroke.
TABLE 5.2 POSITION OF PIN IN EXPANDER ARMS
TYPE OF BRAKE SYSTEM
PIN POSITION FRONT
AXLE [mm] (C)
PIN POSITION REAR
AXLE [mm] (D)
Single conduit system
Double conduit system
Hydraulic system
150
150
150
200
200
200
5.2.8 CHANGE OF PARKING BRAKE CABLES AND ADJUSTMENT OF CABLE
TENSION.
Proper operation of the parking brake is dependent on the effectiveness of the axle brake
and the correct brake cables tension.
Replacing the parking brake cable
Hitch the trailer to tractor. Park trailer and tractor on level surface.
Place wheel chocks under trailer wheel.
Fully unscrew the bolt of the brake crank mechanism (1),
Dismantle shackles, remove pins of guide rollers (4),
Unlock and remove crank mechanism pin (1),
Loosen nuts of cable clamps (2).
Dismantle cable (3).