Doosan DCT20BS, Эксплуатация и обслуживание

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DISASSEMBLING THE DCT20BV AND DCT20BS PAVING BREAKER
GENERAL INSTRUCTIONS
• Clean the breaker outer surface.
• Do not disassemble the breaker any further than
necessary to replace or repair damaged or worn parts.
• Whenever grasping a breaker or a part in a vice, always
use leather or copper-covered vice jaws to protect the
surface of the part and help prevent distortion. Take extra
care with threaded parts and housings.
• Do not remove any part that is a press fit in or on a
subassembly unless the removal of the part is necessary
for repairs or replacement.
• Do not disassemble the breaker unless a complete set of
and O-rings is available for replacement.
DISASSEMBLY OF THE FRONTHEAD
Remove nut (25) and fronthead pinch bolt (24) from the
fronthead (3). Lightly tap the fronthead (using a hide mallet if
necessary) from the cylinder (1).
Press or drift out the two fronthead spring pins (22, 23) and
remove the latch (6).
The plunger (20) and the plunger spring (21) can be removed
from the fronthead.
Handle Disassembly (BV and BS models)
Using a hide mallet tap loose and remove the muffler (29)
and the muffler ring (32) from the cylinder.
Firmly grip the cylinder upright in a vice with leather or
copper covered jaws.
Loosen the four handle nuts (27), remove four washers (40),
unscrew and remove the four handle screws (26).
Lift the handle assembly (5) or (42) from the cylinder (1) (tap
with a hide mallet if necessary).
For BV models only:
Press or tap out the handle pivot pin (12), remove both
handle levers (8 and 9) from the handle body (5) together
with the trigger (7).
Tap out the sleeve (13) to detach the handle levers from
each other.
Remove the handle springs (11) from the handle body (5).
If it is necessary to remove the handle lever stop (14), use
a punch of a suitable size (Ø15 to 19 mm) and drift the stop
out from the cylinder side.
It is possible to remove the trigger pin (15) at this stage if
required.
Unscrew the inlet bushing (18), and remove trigger spring
(17) the trigger ball (16) and throttle pin (15).
Remove the handle screws (40) and washers (39) (if fitted)
and remove the handle grips (10). It may prove easier to cut
off the old handle grips if they are to be replaced.
For BS models only:
Drift or press out the spring pin (45) and remove the trigger
lever (44).
The trigger pin (46) may be removed at this stage if required.
Removal of the handle bar (43) from the casting should
not normally be necessary. If this is required first cut off the
rubber hand-grips (10) and drift or press out the lock spring
pin (45).
Securely support the handle body (42) beneath a press and
using a suitably sized pressing bar, press the handle bar out
of the handle body.
Unscrew the inlet bushing (18), and remove trigger spring
(17) the trigger ball (16) and trigger pin (46).
Remove the handle screws (40) and washers (39) and
remove the handle grips (47). It may prove easier to cut off
the old handle grips if they are to be replaced.
CYLINDER DISASSEMBLY
Remove the spacing washer (30) and valve plate (31).
Slide valve ring (34) from cylinder (1).
Remove sealing ring (28).
Release the cylinder from the vice, invert and allow the
piston (4) to slide out and be caught.
The nozzle (2) is pressed in the cylinder and retained with
Loctite 601 – do not disassemble unless replacement is
necessary.
The cushion bushing (33) is pressed in the cylinder – do not
disassemble unless replacement is necessary..