12-120
170-3 SERIES
TROUBLESHOOTING
Confirm recent repair history
Degree of use of machine Operated for long period
Fuel must be added more frequently
Engine oil smells of diesel fuel
There is oil in cooling water
When engine is first started, drops of water come from muffler
When radiator cap is removed and engine is run at low idling, an abnormal number of bubbles
appear, or water spurts back
Exhaust smoke is white
Water pump drain hole (breather hole) is clogged
When water pump drain hole (breather hole) is cleaned, water comes out
Oil level goes down in clutch or damper chamber
Oil level goes down in hydraulic tank
Questions
Carry out pressure-tightness test of aftercooler
When compression pressure is measured, it is found to be low
Carry out pressure-tightness test of cylinder head
Inspect cylinder block, liner directly
Inspect rear oil seal directly
Carry out pressure-tightness test of oil cooler
Inspect water pump directly
Inspect thermostat directly
Inspect fuel pump directly
Inspect injector directly
Inspect pump auxiliary equipment (pump, compressor) directly
Troubleshooting
Replace
Replace
Replace
Replace
Replace
Correct
Replace
Replace
Correct
Replace
Correct
Replace
Remedy
Broken aftercooler core
Broken cylinder head, head gasket
Defective cylinder head injector sleeve
Cracks inside cylinder block
Damaged cylinder liner O-ring, holes caused by pitting
Broken, broken rear oil seal face
Broken oil cooler core, O-ring
Clogged water pump drain hole (breather hole), defective seal
Defective thermostat seal
Worn fuel pump seal
Cut, worn injector O-ring
Defective auxiliary equipment (pump, compressor) seal
Causes
Check items
S-13 Oil level rises
★ If there is oil in the cooling water, carry out Troubleshooting S-11.
General causes why oil level rises
• Cooling water in oil (milky white)
• Fuel in oil (diluted, and smells of diesel fuel)
• Entry of water or oil from other component
S-13
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