Since the invention of the first turbocharger in 1905, the automotive world has never been the same again, due to the immense amount of power a simple turbo can add to a combustion engine. But since 1905 the same question has been asked time and time again. Are turbos reliable or do they break easily?
Less than 1% of turbos fail due to manufacturing defects. The reason why turbos fail is either because of poor maintenance or damage caused by foreign objects entering the turbo. Oil starvation and oil contamination are what kill 95% of turbochargers. So yes turbos are reliable if properly maintained.
Unfortunately, a lot of people don’t understand the importance of keeping their engine serviced but regular servicing will save you money in the long run.
Most turbos are a relatively simple design with very little to go wrong. All a turbo needs to stay in good working mechanical order is a constant supply of clean oil, but without that oil, the turbo will fail within minutes.
A turbo depends on oil to keep its internal parts lubricated while there spinning at over 350,000 RPM. If you starve the turbo of oil it won’t take long for the internals to get extremely hot and distort. This will eventually lead the turbo to run dry and seize up solid or wear itself away due to having steel on steel with no oil to lubricate the moving parts.
There are two reasons why a turbo might become starved of oil:
- The oil level in the engine has dropped to low and the engine cannot build the correct oil pressure to circulate the oil throughout the turbo sufficiently.
- The most common reason I see is because of not keeping the engine serviced and the oil becomes thick and contaminated, this seriously limits the oil pump’s ability to successfully distribute the oil throughout the engine and turbocharger, it also blocks up the oil pick up pipe in the oil pan making it harder for the pump to suck up the oil.
Journal-bearing turbos are especially prone to failure because of oil starvation, this is because a journal-bearing turbo depends on a high flow of oil and high oil pressure to keep the turbine/compressor shaft floating, centered, and free to rotate.
To find out more about journal bearing turbos you should check out this article it covers the subject a little deeper.
Because, unlike the ball-bearing turbo which uses bearings to keep the shaft rotating freely, the journal-bearing turbo uses oil instead. Ball-bearing turbos need far less oil to stay lubricated but they can still cause problems due to coking on the inside of the turbo housing largely due to not letting the turbo cool down before shutting off the engine.
The other thing that kills a turbo is foreign objects entering the housing of the turbocharger and causing damage to the turbine or compressor. When the compressor wheel inside the turbo is spinning over 350,000 RPM you can imagine the damage that would be done if a stone or any objects got sucked in.
That’s why you should never run your turbo without an air filter because even if the tiniest object flies up off the road and enters the turbo it will lead to catastrophic turbo failure, and possibly engine failure if the turbo disintegrates and the engine sucks in the fragments on the in stroke.
So to answer the original question the answer is yes turbos are very reliable once you understand how they work and you keep them well-maintained. If your interested in finding out more about exactly how a turbo works you should check out this article iv recently wrote covering in detail the mechanics of a turbocharger, I think you’ll enjoy it.
How to Prolong the Life of Your Turbo
The easiest way to prolong the life of your turbo is to keep your engine serviced as per manufacturers’ guidelines. The next thing to do is ensure that you always follow the correct start-up and shut-down procedures for a turbo engine, and if you are unsure of this procedure you need to check out this article which covers the correct procedure in full.
Another important thing to remember when getting a service is to always use good quality oil that the manufacturer recommends for the specific model of automobile.
If you use oil that is too thick you will have issues with circulation and oil starvation but if you use oil that is too thin the oil will just burn and won’t provide the correct level of lubrication needed to keep everything spinning as it should, so it’s important not to go cheap when buying engine oil because it will cost you in the future.
To be in with the best chance of prolonging the life of your turbo you need to take a look at this article covering the 7 things you should not do with a turbo engine, EVER.
Can a Turbo Be Repaired
Most turbos can be repaired depending on the damage that has been done to them. Things like oil seals and bearings can be easily replaced with new ones from the manufacturer.
But if you are unlucky enough for your turbo to have sucked in a foreign object it would not be worth repairing as replacing it with a new turbo would be the most economical option due to every internal part of the turbo would need to be replaced and then there is still no guarantee that they housing is 100%.
If inside the housing got damaged and the surface on which the turbine shaft sits became scored or damaged then the housing is useless and needs to be replaced because the shaft and bearings sit correctly and would not rotate as smoothly or as freely as they should which would cause catastrophic damage to the turbo when spinning at 350,000 RPM.
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