Komatsu PC200-8M0 Shop Manual page 392

SEN06127-00
a Measuring condition and method of
judgment: If the output pressures are
the following values, the PC-EPC
valve is normal.
Operation of
Engine
All control
Low idle
levers and
pedals in
High idle
5) After finishing measurement, remove the
measuring tools and return the removed
parts.
Adjusting
Adjusting pump PC valve
a If either of the following phenomena occurs
and the PC valve seems to be defective, adjust
PC valves (7) and (8) according to the proce-
dure shown below.
As the working load increases, the engine
q
speed lowers remarkably.
q The engine speed is normal but the work
equipment speed is low.
(7): Front pump PC valve
q
q (8): Rear pump PC valve
a The width across flats of the PC valve locknut
is 13 mm and that of the adjustment screw
(inside width) is 4 mm.
Do not turn any other locknuts or adjustment
screws since they affects the hydraulic pump
performance.
40
30-101
Output pressure
lever
Approx. 2.9 MPa
{Approx. 30 kg/cm
0 MPa
neutral
2
{0 kg/cm
Testing and adjusting oil pressure in pump PC control cir-
1. Loosen locknut (9).
a Before loosening the locknut, make coun-
ter mark at the adjustment screw end so
that you can see the position of the lock-
nut before the adjustment (and you can
return the locknut to its original position
after turning it in reverse).
2
}
2. Turn adjustment screw (10) clockwise or coun-
terclockwise to adjust.
}
a Turn the adjustment screw
q
q
3. Tighten locknut (9).
3
Locknut: 27 to 34 Nm {2.8 to 3.5 kgm}
4. After finishing adjustment, check again that the
PC valve output pressure (servo piston inlet
pressure) is normal according to the above
described measurement procedure.
101 Testing and adjusting, Part 1
Clockwise when the work equipment
speed is low (to in crease pu mp
absorption torque) and
Counterclockwise when the engine
speed lowers (to decrease pump
absorption torque).
PC200, 200LC, 220, 220LC-8M0