Howo Truck Turbo Charger Problem Diagnosis and Maintenance.

Turbo Problems Diagnosis

#1 Phenomenon:

When idling, the exhaust smoke is blue. No blue smoke during driving. No oil leaking.
Possible reason:
The impeller shaft of the turbocharger is poorly sealed.

#2 Phenomenon:

Blue smoke is emitted when idling and driving, and it is more serious when accelerating, and the oil consumption is large.
Possible reason:
Exhaust pipe of turbo is blocked.

Three key components in turbo: compressing blade, impeller shaft and turbo blade.

#3 Phenomenon:

The oil consumption is large, but the exhaust smoke is normal and the power is not reduced.
Possible reason:
Oil leakage at the exhaust end, the sealing ring maybe damaged.

#4 Phenomenon:

High oil consumption, blue smoke from the exhaust, but no drop in power.
Possible reason:
Oil leakage inside air compressing end, oil seal is damaged, oil leaked from impeller shaft to new air route.

#5 Phenomenon:

The exhaust smoke is black, engine power drops, and the supercharger makes abnormal noise.
Possible reason:
(1) If there is a metal friction sound, it is caused by the excessive wear of the turbocharger rotor bearing or thrust bearing, so the sound is from friction between the impeller shaft and the shell.
(2) If it is not the metal friction sound but the airflow sound, it is the air leakage caused by the poor connection at the inlet or exhaust ends.

Carbon deposits on shaft.

Turbocharger Maintenance

Install correctly.
Before installing the turbocharger onto engine, you should fill the turbo with oil first, especially the centre impeller shaft.
So when the engine is started, there is already enough oil inside turbo.
After an engine is overhauled, a new turbocharger must NOT be installed.
You need to install the old turbocharger, start the engine, run it for 15 minutes, and then replace the old turbocharger with new one.
Because there are impurities in the engine oil after overhaul, it is necessary to filter the impurities in oil filter first, otherwise, the impurities will block and damage the turbocharger.
Don’t use mineral oil and semi-synthetic oil.
The high temperature of the turbocharger will invalidate all mineral oils and most semi-synthetic motor oils. Therefore, turbocharged models must use fully synthetic engine oil.
Use better quality oil filters and air filters, and replace them regularly.
When a cold car is started, do not accelerate immediately.
It should be idling for 3 to 5 minutes, to allow new oil flow in and out the turbo.
When the vehicle is stopped, especially after a long trip, don’t shut down the engine immediately.
It should be kept idling for at least 5-10 minutes, then shut it down.
Since the shaft of the turbocharger is still at a high temperature, and if the oil stop flowing (engine is shut down), it will easily cause ablation, seizure and carbon deposits inside turbo.

Carbon deposits at exhaust pipe.

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