Komatsu ecot3 PC300LC-8 Shop Manual page 382

SEN02625-06
4) Measure the hydraulic oil pressure with all
the control levers kept in the NEUTRAL posi-
tion and the engine running at high idle and
at low idle.
a You can assume that the PC-EPC valve
output pressure is normal when the fol-
lowing changes are observed.
Engine Control lever
speed
Low idle
High idle
Adjustment
a When a trouble on the PC valve is suspected be-
cause of the following phenomena, adjust PC
valves (6) and (7) in the following manner.
q As workload increases, the engine rpm
sharply drops.
q The engine rpm is normal but the work equip-
ment speed is low.
1. Loosen locknut (8) and turn holder (9) to adjust
the pump absorption torque.
a Turning the holder clockwise increases the
pump absorption torque. Turning the holder
counterclockwise decreases the pump ab-
sorption torque.
a Following indicates the range of adjustment
available from the adjusting screw.
Counterclockwise: Within 1 turn
Clockwise: Within 1/2 turn (Within 180
3
Locknut: 27 - 34 Nm {2.8 - 3.5 kgm}
42
Hydraulic oil
pressure
2.9 MPa
2
{30 kg/cm }
Neutral
0 MPa {0
2
kg/cm }
)
°
2. After the adjustment, make sure that the PC
valve output pressure (servo piston inlet pres-
sure) is normal using the measurement steps
explained earlier.
30 Testing and adjusting
PC300, 350-8