TechCheck - the technical series
Turbochargers need to be handled with care
A turbocharger provides for improved performance and greater efficiency. That’s why nowadays almost all internal combustion engines are “turbocharged”, and as such can achieve the same or even higher output with a smaller swept volume than with a naturally aspirated engine without turbocharger—and that, even with a lower fuel consumption and fewer emissions. This approach is called downsizing, a trend that has found its way into the automotive world in recent years.
Turbochargers are like race horses. They deliver outstanding performance, but are demanding. Because they can reach their maximum speed within seconds, it is important that their core component, the so-called rotating assembly, is perfectly supplied with oil. With warm engines this is not a problem. However, in cold engines the oil is extremely viscous. The consequence: the system is not sufficiently lubricated; the components can rub against each other and wear out more quickly.
Warming up is important
That is why a turbo car should only be driven at high engine speeds when the engine is warm. However, letting the engine idle for this purpose is not a good idea. Viscous oil coupled with low oil pressure at low engine speeds does as much harm to the turbo rotor as a cold start at full throttle. The right way: for the first few kilometres, drive your car at a speed between 1,000 and 2,500 rpm.
What few people know: after a fast drive, a turbo car should not be turned off immediately but should still be kept running for at least half a minute. This is because very high temperatures are generated in the exhaust gas turbine when driving under high load. If the heat remains in the system, oil may burn directly in the turbocharger or in the supply and return lines. This produces so-called oil carbon, which clogs the lines and rubs like sandpaper on the engine parts.
Turbochargers are quickly offended if their needs are ignored. Admittedly, they don’t always show it straight away. If, one day, blue smoke comes out from the exhaust, the car does not pull properly despite full throttle, or the oil consumption increases dramatically, there could be damage in the turbocharger. This means you need to take your car to the repair shop immediately.
Ensure original spare parts are used
Our turbochargers are also available as spare parts. MAHLE also supports workshops with technical training, electronic catalogues and damage brochures, and the Technical Messenger.
Tips on changing turbochargers (Technical Messenger 09/2013) [PDF; 253 KB]
Turbocharger technology (article on page 12 of our customer Magazine MAHLE Aftermarket News 1/2014) [PDF; 5474 KB]
MAHLE Original turbochargers