Measuring And Adjusting Oil Pressure In Pump Pc Control Circuit - Komatsu PC210-8 Shop Manual

UEN00228-04
Measuring 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 residual pressure from
the hydraulic circuit. For details, see
"Releasing residual pressure from hydrau-
lic 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 basic pressure of the control circuit are nor-
mal.
a Measure the oil pressure in the pump PC con-
trol circuit under the following condition.
Hydraulic oil temperature: Within operating
q
range
1. Measuring PC valve output pressure (servo
piston inlet pressure)
a Measure the PC valve output pressure
(servo piston inlet pressure) and pump
discharge pressure simultaneously and
compare them.
1) Open the side cover of the pump room
and remove oil pressure pickup plugs (1),
(2), (3), and (4).
(1): Front pump discharge pressure
q
pickup plug
(2): Rear pump discharge pressure
q
pickup plug
(3): Front PC valve output pressure
q
pickup plug
(4): Rear PC valve output pressure
q
pickup plug
32
Part name
O-ring
PC210/230-8
1
4
PC240-8
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 gauges of 58.8
MPa {600 kg/cm
PC210/230-8
L2
L2
30 Testing and adjusting
2
1
Warning:Test points reversed
on PC210/230-8 pump
2
}.
1
PC210, 230, 240-8
3
L2