CFE - Turbo Troubleshooting

Kebetulan ada kawan tanya pasal exora turbo problem. Bolehla share kat sini.

Common Turbo Problem = Turbo rosak, oil leaking, turbo jammed, asap putih keluar kat exhaust
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Common root causes:
1.Excessive heat
2.Excessive oil deterioration
3.Others: Debris in oil system, poor oil quality,blockage n etc
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This root causes lead to:
Turbo shaft bent. When turbo shaft bent and wobble at 250,000rpm and above...turbo shaft oil seal will be destroyed = oil will leak = when there’s less oil to lubricate = catastrophic failure and turbo will seize
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1.Excessive heat
Why excessive heat? = oil deteriorate over time of usage. Oil must be changed on time. There’s a reason to the oil change interval. Mineral oil will deteriorate at its design limit near 5000km mileage (normal guideline).
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When oil deteriorates, it cannot dissipate heat enough. When heat cannot be dissipated, the increase in temperature will cause lower oil pressure and oil film thickness to break.
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Poor oil film thickness, low oil pressure = poor lubrication = metal to metal contact on rotating parts = failure.
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Solution = Discipline oil change according to specified interval, oil cooler with thermostat, high quality oil, frequent turbo oil line servicing n etc
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2.Excessive oil deterioration
What happen when excessive oil deterioration = it cannot dissipate heat enough. When heat cannot be dissipated, the increase in temperature will cause lower oil pressure and oil film thickness to break. Poor oil film thickness, low oil pressure = poor lubrication = metal to metal contact on rotating parts = failure.
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Solution = Discipline oil change according to specified interval, oil cooler with thermostat, high quality oil, frequent turbo oil line servicing n etc
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Other cases/causes that can reduce the oil quality:
-Water dilution in oil
-Fuel/combustion bi-product dilution in oil


But both of these causes should be rare/severe cases in normal passenger cars. Because water dilution might be caused by internal water leakage in the system. While fuel dilution might be caused by excessive blowby gases/combustion bi-product that escaped through the piston ring during engine operation.
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Just sharing my experience around 10 years in conducting 600 hours Engine Durability Testing and Oil Pressure Study.