Almost every diesel car nowadays uses a turbocharger. In case of petrol it’s not a norm yet, however with stricter emission norms, and desired fuel-economy (under CAFE norms) will only put pressure on manufacturers to employ them in case of petrol engines too. While turbo may offer better economy and power, its design however is inherently complicated which requires you take some precautions.
They may not fail on their own due to some inherent design flaw and are quite robust that way, but there are certain things that can shorten their overall service life drastically.
1. How does Turbo work, why is lubrication critical?
In case of turbo, there’s an exhaust driven turbine which spins to create boost for the engine and pushes more air inside the combustion cylinder than what the engine can do on its own. Unlike an engine which responds under the throttle and has a redline of around 6000-7000 RPM, a turbo can spin at speeds in excess of over 2,00000 RPM. Also, it generally does not use bearings and relies on brass bushings. Therefore, lubrication requirements are critical to the life of the turbocharger. Read - How turbo increases the power of an engine and why is there a lag.
2. What can reduce the life of Turbo?
Since lubrication is of utmost importance, delayed oil change can be detrimental to turbo’s life. Turbo’s bush bathes in engine oil and is lubricated by a thin film of pressurised oil. Oil Pressure drop even for a moment can be catastrophic and can cause excessive wear and tear.
In case of an engine, a gentle warm up and cool down ensures longevity, however if you don’t do it, it does not damage the engine and it would still serve a considerable life. While in case of turbo, temperatures can reach in the range 160-180 degrees. Unlike engine which stops immediately as soon as you shut the ignition, a turbo keeps on spinning due to inertia even after the engine is shut. Therefore, no cool down in case of a turbo can cause premature failure since lubrication of the turbo requires a running engine.
3. What can cause turbo failure?
A lot of factors can cause the turbo to fail. Engine oil contamination, also known as coking can result in case the engine is not properly cooled down and shut abruptly. It’s the foremost reasons that can premature failure. The engine oil which is supposed to cool the turbocharger gets heated and causes solidified deposits which ultimately blocks passages and causes failure.
4. What can you do to extend turbo’s life?
Firstly, you should get the oil change as and when recommended. Second, gentle warm up is not only good for the engine but it also benefits the turbo, so make sure that you warm up the engine gently by idling for a minute or so, and drive slowly without lugging the engine for the first five minutes. And last, but certainly not the least, always allow the engine and turbo to cool down. Before shutting the engine, let it idle for a minute or two or as advised by the manufacturer.