Adjusting The Braking System - Bottarini GDP21 Maintenance And Operating Manual

15. Undercarriage
Over-run hitches
KNOTT over-run hitches are available
for both hydraulic and mechanical brakes.
Handbrake lever with power reservoir,
code „KH"
With the type "KH" the spring reservoir is
under torsion at the centre point. If the
handbrake is applied, then it works
automatically and requires almost no
force. The system is designed so that
when the handbrake is applied, sufficient
energy is stored within the spring. When
transmitted through the brake rods this
prevents the brake shoes from slipping
away from the brake drum.

15.5 Adjusting the braking system

15.5.1 Preparations
*
Jack up the trailer
* Release the handbrake
* Pull out the drawbar [5] of the overrun-
system as far as it will go
6
Fig. 50 KNOTT overrun brake
1
Contact-breaking cable
2 Trailer coupling ring (varies by type)
3
Handbrake lever
4 Transmission lever
5 Drawbar and bellows
Danger
When any disconnection of the braking
system takes place, secure handbrake
lever by reinserting the security bolt
[15] (see warning plate [16]).
16
15
Fig. 51
15 security bolt
16 Warning plate
52
15.5.2
Preliminary requirements:
* When carrying out adjustments, always
start with the wheel brakes.
*
When carrying out adjustments, turn
the wheel only in the direction of
forward travel.
* Insert the security bolt [15] (see
warning plate)!
* Do not pre-tension the expanding
locking mechanism in the brake. If
necessary, loosen the brake linkage [6]
at the brake compensator [8].
* Check the expanding locking
mechanism and control cable [11]
for ease of movement.
Attention
*
The compression spring [7] may
only be lightly pre-tensioned and
must not become fully compressed
when activated!
*
Bowden cable [14] must not activate
brake.
* Never readjust the braking system
or brakes by the brake linkage [6] or
turnbuckles (if fitted) in the linkage!
15.5.3
Adjusting the brake
Fig. 52 KNOTT wheel brake
12
Adjusting screw
13 Cable entry
Tighten the adjusting screw [12] (on the
outside of the brake plate, opposite the
cable entry [13]), turning clockwise until
the wheel can only be turned with difficulty
or not at all.
Wrench sizes for adjusting screws [12]
Brake size
160x35 / 200x50
250x40
300x60
Ease off the adjusting screw [12] in the
anticlockwise direction (approx. 1/2 turn)
until the wheel turns freely. Slight rubbing
noises, which do not effect the free turning
of the wheel, are permitted.
When the brake is correctly adjusted,
the actuating travel of the control cable
[11] will be 5-8 mm.
Carry out the adjustment procedure,
as described, on all the wheel brakes
in succession.
15.5.4 Adjusting the brake
compensating system
Fig. 53 KNOTT transmission system for
tandem and single-axle chassis.
6
Brake linkage
7 Compression spring
8
Compensating balance assembly
9
Compensating balance (tandem) or
master compensator
10
Compensating balance (single axle)
11 Control cable
14
Fig. 54 KNOTT transmission system for
tandem and single-axle chassis.
14 Bowden cable for handbrake
*
Insert the security bolt [15] (see
warning plate)!
Wrench size
* Remove the bowden cable [14].
SW 17
*
Preadjust the length of the brake
SW 19
linkage [6] (slight play permitted).
SW 22
* Insert the bowden cable [14].
* Remove the security bolt [15].
*
Operate the handbrake lever [3] and
check the position of the compensating
balances [9 and 10]. They should be at
right angles to the direction of towing.