Geely JL481Q, Manual

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IV. Exhaust Smoke from Exhaust Pipe
Is Abnormal (or with Unusual Odor)
When combustion system of an engine fails, smoke discharged from exhaust pipe is abnormal in color.
1. Exhaust Smoke Is Very Dark
This is caused by incomplete combustion, gas mixture is too thick to be combusted completely, and certain gasoline is
discharged even without combustion, which leads to decrease of engine power. Now it is necessary to adjust concentration
of gas mixture in time, check fuel pressure adjuster, throttle position sensor, injector and ECU system and make correc-
tions.
2. Exhaust Smoke Is Blue with Unusual Odor
This is indicative of the substantial existence of engine oil vapor in the exhaust gas. Engine oil enters cylinder and partici-
pates in combustion. The main cause is that oil piston ring is not scraped neatly, and abraded improperly, now replace the
oil ring; it is also possible that valve oil seal is defective or the spacing between valve stem and bushing is too large, so that
oil enters combustion chamber to participate in combustion. In this case, it is necessary to replace oil seal or bushing to
return to normal condition.
Item Symptom Cause Elimination method
Insufficien
t coolant
Defective
radiator
Defective radiator hose
Defective radiator hose band
Defective head gasket
Crack on cylinder body
Defective seal of water pump
Antifreeze not replaced
Defective thermostat Replace antifreeze
Replace the thermostat
Clogged cooling pipe
Poor ventilation
Voltage irregularity
Temperature control switch
of radiator fails
Water jacket clogged due to
excessive scale deposits
Oil in engine is not sufficient
(Oil leakage or not filled in time)
If oil leak exists, repair oil sump or
replace it;
If not filled in time, fill up engine oil
Water pump failure
Repair or replace water pump
Poor fan
Check and eliminate, if the motor fails,
replace it
Replace it
Repair and dredge it
Repair and dredge it
Improve ventilation
Welding peeling-off Repair welding
Imperfect cooling
Water leakage
Water leakage
Replace it
Repair welding, otherwise replace it
Replace it
Use impregnation process for remedy or
replace it
Replace seal
Evaporation exists due to imperfect
radiator cap
Pinholes caused by
corrosion
Fill pinholes with vanish, otherwise
replace it
Repair, replace
10. Engine Overheats
170