Testing And Adjusting Oil Pressure In Pump Pc Control Circuit - Komatsu PC200-8M0 Shop Manual

SEN06127-00
Testing and adjusting oil pressure
in pump PC control circuit
a Measuring and adjusting tools for oil pressure
in pump PC control circuit
Symbol Part No.
799-101-5002 Hydraulic tester
1
790-261-1204 Digital hydraulic tester
L
799-101-5220 Nipple (10 × 1.25 mm)
2
07002-11023
k
Stop the machine on a level ground and
lower the work equipment to the ground.
Then, release the remaining pressure from
the hydraulic circuit. For details, see
" R e l e a s i n g r e m a i n i n g p r e s s u r e f r o m
hydraulic circuit".
Measuring
a Before measuring the oil pressure in the PC
control circuit, check that the oil pressure in the
work equipment, swing, and travel circuits and
the control circuit source pressure are normal.
a Measure the oil pressure in the pump PC con-
trol circuit under the following condition.
q Hydraulic oil temperature: Within operating
range
1. Measuring of PC valve output pressure
(servo piston inlet pressure)
a Measure the PC valve output pressure
(servo piston inlet pressure) and pump
discharge pressure simultaneously to
compare them.
1) Open the side cover of the pump room
and remove oil pressure pickup plugs (1),
(2), (3), and (4).
q (1): Front pump discharge pressure
pickup plug
q (2): Rear pump discharge pressure
pickup plug
(3): Front PC valve output pressure
q
pickup plug
q (4): Rear PC valve output pressure
pickup plug
38
30-101
Part name
O-ring
Testing and adjusting oil pressure in pump PC control cir-
1
2) Install nipples L2 and nipples [1] of
hydraulic tester L1 and connect them to oil
pressure gauges [2].
a Connect the measuring part of plug
(3) by using joint (790-301-1271) and
elbow (790-301-1530) of hydraulic
tester L1 and nipple [1] so that it will
not interfere with the drain piping.
a Use the oil pressure gauge of 60 MPa
{600 kg/cm
3) Start the engine and operate the arm cyl-
inder to the IN stroke end.
4) Set the working mode in the power mode
(P) and turn the swing lock switch ON.
a If the swing lock switch is turned ON,
the main relief valve is set for high-
pressure relief.
101 Testing and adjusting, Part 1
2
}.
PC200, 200LC, 220, 220LC-8M0