Doosan 12/154, Operation & Maintenance Manual

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MAINTENANCE 65
12/154
The brake actuators must not be pre-tensioned - if necessary loosen
the brake linkage [7] on the brake equalisation assembly [8].
Check that brake actuators and cables [11] operate smoothly.
2. Brake Shoe Adjustment
Tighten adjusting screw [12] clockwise until the wheel locks.
Loosen adjusting screw [12] anti-clockwise (approx. ½ turn) until the
wheel can be moved freely.
Slight dragging noises that do not impede the free movement of the
wheel are permissible.
This adjustment procedure must be carried out as described on both
wheel brakes.
When the brake has been adjusted accurately the actuating distance
is approximately 5-8mm on the cable [11].
3. Compensator assembly adjustment
Variable Height models
Fit an M10 safety screw to the handbrake pivot.
Disconnect the handbrake cable [5] at one end.
Pre-adjust brake linkage [7] lengthways (a little play is permissible) and
re-insert the cable [5], adjusting it to give a small amount of play.
Remove the M10 safety screw from the handbrake pivot.
All Models
Engage the handbrake lever [1] and check that the position of the
equaliser plate [10] is at right angles to the pulling direction. If
necessary correct the position of the equaliser plate [10] on the cables
[11].
The compression spring [9] must only be slightly pre-tensioned and
when engaged must not touch the axle tube.
4. Brake linkage adjustment
Adjust the brake linkage [7] lengthways without pre-tension and without
play in the transmission lever [4].
Readjustment
Engage the handbrake lever [1] forcefully a number of times to set the
brake.
Check the alignment of the equalisation assembly [8], this should be at
right angles to the pulling direction.
Check the play in the brake linkage [7].
If necessary adjust the brake linkage [7] again without play and without
pre-tensioning.
There must still be a little play in cable [5] (Variable Height Only).
Check the position of the hand brake lever [1]. The start of resistance
should be approximately 10-15mm above the horizontal position.
Check that the wheels move freely when the handbrake is disengaged.
Final test
Check the fastenings on the transmission system (cables, brake
equalisation system and linkage).
Check the handbrake cable [5] for a small amount of play and adjust if
necessary (Variable height only).
Check the compression spring [9] for pre-tensioning.
Test run
If necessary carry out 2-3 test brake actions.
Test brake action
Check the play in brake linkage [7] and if necessary adjust the length
of brake linkage [7] until there is no play.
Apply the handbrake while rolling the machine forward, travel of the
handbrake lever up to
2
/
3
of maximum is allowed.
RE-ADJUSTING THE OVERRUN BRAKING SYSTEM
(KNOTT RUNNING GEAR)
Re-adjustment of the wheel brakes will compensate for brake lining
wear. Follow the procedure described in
2: Brake Shoe Adjustment.
Check the play in the brake linkage [7] and re-adjust if necessary.
Important
Check the brake actuators and cables [11]. The brake actuators must
not be pre-tensioned.
Excessive operation of the handbrake lever, which may have been
caused by worn brake linings, must not be corrected by re-adjusting
(shortening) the brake linkage [7].
7. Brake linkage
8. Equalisation assembly
9. Compression spring
10.Equaliser plate
11.Cable
CAUTION: The compression spring [9] must only be lightly pre-
tensioned and when operating must never touch the axle tube.
Never adjust the brakes at the brake linkage [7].
12.Adjusting screw
13.Cable entry
Width across flats of adjusting screw [12]
Brake size Key width
160x35 / 200x50 SW 17
250x40 SW 19
300x60 SW 22