Machine Is Not Steered Well Or Steering Power Is Low - Komatsu PC210-8 Shop Manual

UEN00245-02
H-20 Machine is not steered well or steering power is low
Trouble

• Machine is not steered well or steering power is low

Related
• Carry out all troubleshooting in power mode (P) of working mode.
information
Malfunction of travel PPC
1
valve (steering spool)
Malfunction of travel
2
junction solenoid valve
Malfunction of travel
3
junction valve
Malfunction of merge-divider
4
main EPC valve
Malfunction of merge-divider
5
Possible
LS-EPC valve
causes and
Malfunction of merge-divider
6
standard value
main valve
in normal state
Malfunction of merge-divider
7
LS valve
Malfunction of travel control
8
valve (spool)
Malfunction of travel control
9 valve (pressure compensa-
tion valve)
Malfunction of travel control
10
valve (suction valve)
Malfunction of bucket control
11
valve (LS shuttle valve)
Defective seal of check valve
12 of LS pressure sensing part
(control valve side)
Defective seal of travel
13
motor (safety valve)
Defective seal of travel
14
motor (check valve)
22
Cause Standard value in normal state/Remarks on troubleshooting
a
a
Travel junction valve may have malfunction. Check it directly.
Merge-divider main EPC valve may have malfunction. Check it
directly.
Merge-divider LS-EPC valve may have malfunction. Check it
directly.
Merge-divider main valve may have malfunction. Check it directly.
Merge-divider LS valve may have malfunction. Check it directly.
Spool of travel control valve may have malfunction. Check it
directly.
Pressure compensation valve of travel control valve may have mal-
function. Check it directly.
Suction valve of travel control valve may have malfunction. Check it
directly.
LS shuttle valve of bucket control valve may have malfunction.
Check it directly.
Seal of check valve of LS pressure sensing part (control valve side)
may be defective. Check it directly.
Seal of safety valve of travel motor may be defective. Check it
directly.
a
Seal of check valve of travel motor may be defective. Check it
directly.
a
Prepare with engine stopped, then run engine at high idle and
carry out troubleshooting.
Travel lever
Both sides in neutral
Either side operated
Prepare with engine stopped, then run engine at high idle and
carry out troubleshooting.
Travel lever
Both sides in neutral
Either side operated
Motors of same type on forward and reverse sides or on right
and left sides may be checked by replacing them with each
other and seeing change of condition.
Motors of same type on forward and reverse sides or on right
and left sides may be checked by replacing them with each
other and seeing change of condition.
40 Troubleshooting
PPC valve output pressure
(Steering)
0 MPa
{0 kg/cm 2 }
2.84 – 3.43 MPa
2
{29 – 35 kg/cm }
Travel junction solenoid valve
output pressure
0 MPa
2
{0 kg/cm }
2.9 MPa
{30 kg/cm 2 }
PC210, 230, 240-8
1