UNCONTROLLE
D IF P
R
INTE
D
VEHICLE H 983
Issue 1, Jul 11
ELECTRICAL AND MECHANICAL
ENGINEERING INSTRUCTIONS
6
18. Preliminary
Checks.
Prior to carrying out any axle alignment adjustment:
a.
Unload the trailer if fitted.
b.
Ensure that all suspension components are in good condition.
c.
Ensure that all tyre pressures are correct.
d.
Ensure the dolly is on flat, level ground.
e.
Ensure that the dolly has travelled in a straight line for a minimum of 20 metres before checking any
adjustment (this removes any stresses from the suspension components).
19. Adjustment.
To alter the axle alignment:
a.
Loosen the four clamp bolts on the right-hand radius rods.
b.
Rotate the centre section of the applicable radius rod to alter the axle alignment.
NOTE
Dimensions X and Y are to be equal along each side of the trailer.
BRAKE ADJUSTMENT
20.
The correct brake adjustment is obtained when:
a.
The distance from the base of the brake chamber to the centre line of the clevis pin is 185 mm with the
brake released (Figure 2).
b.
The angle formed by the centre lines of the slack adjuster and the brake chamber push rod is
approximately 90° when the brakes are applied.
Figure 2 Slack Adjuster Alignment
c.
The maximum travel of the brake chamber pushrod to apply the brake is less than 40 mm.
21.
To adjust the brakes, depress the locking ring and turn the adjusting screw clockwise until the brake is
applied. Back-off the adjusting screw to achieve the correct adjustment as shown in Figure 2. If necessary, adjust the
length of the brake chamber pushrod to achieve the correct settings.
