Disassembly; Precautions For Disassembly; Disassembling Procedures - Doosan DX140R Shop Manual

DISASSEMBLY

Precautions for Disassembly

1. On a level surface, place the main equipment on the level
and place all other working devices on the ground.
Ensure that neither the traveling nor the swing motion is
self-activated.
Stop the engine and release the pressure from all
actuators.
If the valve assembly is replaced or the valve is
disassembled under pressurized conditions, there is a
danger that high pressure oil may be expulsed or parts
may eject suddenly. When disassembling, ground the
bucket and fully release the pressure in the oil circuit.
2. Release air pressure from the tank.
3. Clean the working place so that no foreign matter can enter
into the valve when disassembling.
4. Tag disassembled parts so that they can be easily and
correctly identified for reassembling.
5. Replace all seals (o-rings, backup rings) with new ones
6. Spools are matched with the respective valve housing and
sleeves. Therefore, spools must not be replaced.

Disassembling Procedures

In this disassembly section, the parts for assembly are identified
by
Disassembly of Main Spool
1. Unscrew the socket head bolt (width across flats of hole:
6), disassemble the long cap.
Remove the o-ring from the groove of the valve housing.
2. Unscrew the socket head bolt (width across flats of hole:
5), disassemble the cap.
Remove the o-ring from the cap.
3. Pick out the spools as in sub-assembly state from the valve
housing.
Main Control Valve
CAUTION
SP001029
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