In researching this article we got feedback from owners of turbocharged airplanes who reported that they had to overhaul the turbos at about 1000 hours of operation and an equal number who said that their turbos ran fine all the way to when they overhauled the engine. We came away with the opinion that an owner who follows good engine operating procedures generally—no rapid power changes, allowing the engine oil to warm up prior to takeoff and changing the oil on a schedule that reflects hours of operation as we’ll as calendar time—can reasonably expect the turbo to make it to engine TBO.
In speaking with various shops and with Mike Busch, whose Savvy Aviation provides maintenance management to several hundred general aviation aircraft owners, we learned that when there is a problem with a turbo system it’s important to carefully troubleshoot the matter rather than blindly replacing components in hopes of fixing things. In general, there are five things that can go wrong with a turbo system: problems with the turbocharger, controller or wastegate, or leaks in the induction or exhaust systems. Most manifest initially with a loss of manifold pressure at altitude or premature bootstrapping (loss of manifold pressure control because the wastegate is closed). The underlying problems tend to have subtly different symptoms, so it’s important to carefully analyze what’s going on.