Komatsu 170-3 Series, Руководство по ремонту, Страница: 167 / 454

12-108-2
170-3 SERIES
TROUBLESHOOTING
Confirm recent repair history
Degree of use of machine Operated for long period
Suddenly failed to start
Starting performance became worse gradually
Starts when engine is warm
Non-specified fuel is being used
Replacement of filters has not been carried out according to Operation Manual
Engine oil must be added more frequently
When preheating, preheating indicator lamp does not light up
Dust indicator is red
Air breather hole in fuel tank cap is clogged
Rust and water are found when fuel tank is drained
When fuel filter is drained, no fuel comes out
There is leakage from fuel piping
Starting motor cranks engine slowly
When engine is cranked, abnormal noise is generated around cylinder head
Fuel pump outlet port coupler is pushed, almost no fuel comes out
Fuel pump outlet port coupler is pushed, air comes out together with fuel
Questions
Inspect air cleaner element directly
Inspect dynamic valve system directly
When compression pressure is measured, it is found to be low
When negative pressure at inlet port of fuel pump is measured, it is found to be high
When fuel filter, strainer directly
Inspect fuel pump directly
Inspect timing rail actuator screen directly
When temperature of exhaust gas of each cylinder is measured, there are some cylinders that are low
When specific gravity of electrolyte and voltage of battery are measured, one of them is low
When starting switch is at HEAT, heater mount does not become warm
Inspect sensor directly (Output voltage and resistance)
Inspect actuator directly (Resistance and filter for clogging)
Inspect fuel rail actuator directly
T
roubleshooting
Clean Replace Replace Clean Clean Clean Replace Replace Replace Replace Correct
Remedy
Clogged air cleaner element Defective dynamic valve system (valve, rocker arm, etc.) W
orn piston ring, cylinder liner
Clogged fuel tank cap Loose piping, fuel filter
, entry of air
Clogged fuel filter
, strainer
Defective fuel pump Clogged timing actuator screen Defective injector Defective or deteriorated battery Defective preheating heater circuit
When engine is
cranked with starting
motor, and
Check items
Causes
c) Exhaust smoke comes out but engine does not start (fuel is being injected)
General causes why exhaust smoke comes out but engine does not start
• Lack of rotating force due to defective electrical system
• Insufficient supply of fuel
• Insufficient intake of air
• Improper selection of fuel and oil
• Defective HPI sensor
• Defective HPI actuator
(10)
S-2
ProCarManuals.com