Vibration Is Excessive - Komatsu ecot3 PC300LC-8 Shop Manual

40 Troubleshooting
S-16 Vibration is excessive
General causes why vibration is excessive
• Defective parts (abnormal wear, breakage)
• Misalignment between engine and chassis
• Abnormal combustion
a
If abnormal noise is made and vibration is excessive, carry out trouble-
shooting for "S-15 Abnormal noise is made", too.
Confirm recent repair history
Degree of use of
Operated for long period
machine
Suddenly increased
Condition of
vibration
Gradually increased
Non-specified oil is being used
Metal particles are found when oil filter is drained
Metal particles are found when oil pan is drained
Oil pressure is low at low idle
Vibration occurs at mid-range speed
Vibration follows engine speed
Exhaust smoke is black
Inspect dynamic valve system directly
Inspect main bearing and connecting rod bearing directly
Inspect gear train directly
Inspect camshaft bushing directly
Check with monitoring function of machine monitor
Inspect engine mounting bolts and cushions directly
When alignment is checked, radial runout or facial runout is detected
Inspect output shaft or inside of damper directly
PC300, 350-8
SEN02634-02
Cause
E E
Q
Q Q
Q Q
w w
w w
Q Q
Q
w Q
q
q
q
q
q
Remedy
1
E
Q
Q
Q Q
Q Q Q
q
q
q
23