Komatsu PC130-7, Shop Manual

Page: 51 / 342

PC130-7
20-133
TESTING AND ADJUSTING
MEASURING SOLENOID
VALVE OUTPUT PRESSURE
a
Measuring instruments for solenoid valve output
pressure
a
Before measuring the solenoid valve output
pressure, check that the basic pressure in the
control circuit is normal.
k
Lower the work equipment to the ground and
stop the engine. Operate the control levers
several times to release the residual pressure
in the piping, and then loosen the oil filler cap of
the hydraulic tank slowly to release the internal
pressure of the hydraulic tank.
1. Remove the undercover of the control valve and
disconnect outlet hoses (1) – (4) of the solenoid
valves to be measured.
a
Since outlet hose (4) of the PPC pressure
lock solenoid valve has a quick coupler,
measure the output pressure on the PPC
valve side.
2. Install adapter M2 and connect the disconnected
hose again.
3. Install nipple [1] of hydraulic tester M1 and con-
nect it to hydraulic gauge [2].
a
Use the oil pressure gauges of 5.9 MPa {60
kg/cm
2
}.
a
The figure shows the measuring instruments
connected to the outlet hose of the 2-stage
relief solenoid valve.
4. Run the engine and heighten the hydraulic oil
temperature to 45 – 55°C.
5. Run the engine at high idling, operate the control
levers and switches to turn the solenoid valve
ON or OFF, and measure the oil pressure.
a
For the conditions for turning the solenoid
valve ON and OFF, see the operations table
of each solenoid valve.
a
The operating condition of the solenoid valve
can be also checked with the monitoring
function [02] of the monitor panel (excluding
the PPC pressure lock solenoid valve).
a
If the output pressure is as follows, the sole-
noid valve is normal.
Symbol Part No. Part name
M
1
799-101-5002 Hydraulic tester
790-261-1203 Digital hydraulic tester
2 799-401-3100 Adapter (Size 02)
No. Solenoid valve to be measured
1 2-stage relief solenoid valve
2 Swing holding brake solenoid valve
3 Travel speed solenoid valve
4 PPC pressure lock solenoid valve
Solenoid valve Output pressure
OFF
(Deenergized)
0 MPa {0kg/cm
2
}
ON (Energized)
Almost same as control basic
pressure
(See standard values table)
MEASURING SOLENOID VALVE OUTPUT PRESSURE
(1)