Power Max. Switch Does Not Operate; In Compound Operation, Work Equipment With Larger Load Moves Slowly - Komatsu ecot3 PC300LC-8 Shop Manual

40 Troubleshooting
H-14 Power max. switch does not operate
Trouble • The power maximizing function does not work.
Related infor-
• Set the working mode in P-mode before start.
mation
Possible causes
Malfunction of 2-stage relief
and standard 1
solenoid valve
value in normal
state
Malfunction of main relief
2
valve
H-15 In compound operation, work equipment with larger load moves
slowly
Failure phe-
• In a compound operation, work equipment with larger load tends to move slowly.
nomenon
Relative infor-
—
mation
Presumed
cause and stan-
Malfunctioning of pressure
dard value in
1 compensation valve for work
normalcy
equipment with smaller load
PC300, 350-8
Cause Standard value in normal state/Remarks on troubleshooting
a
Main relief valve may have malfunction. Check it directly.
Cause Standard value in normalcy and references for troubleshooting
The pressure compensation valve for the work equipment with
smaller load is presumed to malfunction. Check the valve itself.
Combination of compound
Boom RAISE + arm OUT
Boom RAISE + bucket CURL
Arm OUT + bucket CURL
Boom LOWER + arm OUT
Prepare with engine stopped, then run engine at high idle and
carry out troubleshooting.
Swing lock switch
OFF
ON
operation
Boom RAISE + arm IN
SEN02633-03
Solenoid output pressure
2
0 MPa {0 kg/cm }
2.84 – 3.43 MPa
2
{29 – 35 kg/cm }
Work equipment with larger load
Boom RAISE
Arm OUT
Boom RAISE
Arm OUT
Arm OUT
1
1
19