The turbocharger revolves at very high speeds and so it is essential that there is enough oil present to lubricate the thrust and journal bearings, to stabilise the rotating shaft and journal bearings, and to act as a coolant before high turbo charger speeds are reached.
As the turbo speed and the engine load increases, so does the need for oil. If there is even a slight delay in the oil reaching the turbo then failure will occur.
Although the turbo has an oil filter, it cannot be relied on to filter excessively contaminated oil. Dirty oil can cause damage to the bearings, and if the particles are large enough to block the internal oil passage then the turbo can quickly become starved of oil.
Diesel lubrication is an extremely important part of the engine, whilst modern technology has gone a long way in providing good oils, there are still 2 basic issues to navigate.
The high temperatues that are present in the engine can cause the oil to crack, breakdown and generally deteriorate. If the oil begins to breakdown it can produce tarry materials which will stick to the engine rings and cause a range of troubles.
Outside contamination can also cause issues. This is a frequent problem as combustion produces so many contaminants such as ash and soot. Furthermore, foreign bodies from outside the engine can also find there way into the cylinders.
Any materials that enter these systems will undoubtedly damage the turbo and could also damage the engine. The turbochargner is a vulnerable system and any particles that enter the casings can cause damage. It should also be mentioned that any foregin body that stays in the turbo can cause possible loss of power, black smoke, excessive oil usage or leakage, and damaged wheels.
If the turbo has not been fitted correctly then the risk of failure is heightened. Only quality assured materials should be used, and thorough quality checks need to be made on both the matrials and the workmanship, to ensure they meet the OE specifications.
It is a device present in diesel engines that increases engine power and efficiency by forcing air into cylinders.
If the engine is regularly serviced, and high quality oil is used, then the turbo can last as long as the engine. However, problems occur if the turbo is neglected or if foreign particles enter it due to low quality oil.
If your turbo is making loud noises then it is potentially unbalanced, worn out or damaged, and should be seen to.
The most common symptoms of a failed turbo are lack of power, excessive exhaust smoke, whining noises or passing lubricants.
Correctly identifying the turbo means you will get the right replacement first time, therefore saving you money, time and hassle. Look for the label or nameplate on the turbos outer casing. If it is lost or unreadable you may need to make note of the make and model of your car, the engine size and code, the BHP and the reg number in order to enable use to determine the correct turbo for you.