Komatsu F30791, Shop Manual, Page: 156 / 298

PC20R-8
20-40
TESTING AND ADJUSTMENTS
CONTROL AND REGULATION OF THE PRESSURES
IN THE HYDRAULIC CIRCUITS
1. Control of operating pressure (unloading valve)
1 - Remove the plug (1) of pump P1 and mount a
pressure adapter.
2 - Connect a pressure gauge E1 (60 bar).
3 - Start the engine and bring it up to high idling with
all levers in neutral position.
4 - Check the pressure.
H Normal pressure:
35 w 5 kg/cm
2
(34.3 w 4.9 bar)
The unloading valve cannot be re-adjusted. If
the pressure differs from the normal value the
valve must be substituted.
2. Control the operating pressures of the working
equipment, machine travel, and swing
1 - Remove the plug (1) of pump P1 and mount a
pressure adapter.
2 - Connect a pressure gauge E2 (400 bar) or E3
(600 bar).
3 - Start the engine and bring it up to high idling.
4 - Check the pressure for each movement with the
command lever at the end of its stroke and with
the pressure stabilised.
To check the pressure of the working equip-
ment, push the piston to the end of its stroke.
To check the pressure of machine travel, in-
sert a block " A " between the chassis and
the sprocket wheel.
To check the pressures of the swing, insert
the swing lock.
H Normal pressures:
Working equipment and travel:
210 10 kg/cm
2
(206 10 bar)
Swing: 155 5 kg/cm
2
(151.9 5 bar)
PC20R-8 PC27R-8
RKPA2380
1
E
1
RKPA2390
1
E
3
RKPA3870
A