Aircraft engine manufacturers recommend that owners overhaul their engines when the engines have accumulated a set number of flight hours. Depending on the make and model, the "Time Between Overhaul" ranges from 1200 to 2400 hours. No regulation requires the general aviation aircraft owner to comply with the manufacturer’s recommended TBO. As far as the

Aircraft engine manufacturers recommend that owners overhaul their engines when they accumulate a certain amount of operating time, usually between 1200 and 2400 hours depending on the engine’s make and model. For example, Teledyne Continental Motors suggests that owners overhaul its IO-550 model engine at 2000 hours. Textron LycLycoming Engine - photo by wirelizardoming suggests that owners overhaul its O-235 engine, like the one pictured, at 2400 hours.

Overhauls are expensive.  Some can cost $40,000 or more.  An increasing number of owners opt to run their engines 200, 400 or more hours past the manufacturer’s recommended "time between overhauls," or TBO.  Once past TBO, they may take extra precautions by, for example, regularly sending out engine oil samples for spectrographic analysis, checking the engine’s compression, and looking inside certain parts of the engine with a boroscope to insure that  things look good. They feel the manufacturer’s TBO recommendations are somewhat arbitrary. By running their engines past TBO they are squeezing more life out of them, and that just makes good economic sense.

The FAA does not require private owners to comply with the manufacturer’s stated TBO interval. The manufacturer’s TBO is therefore advisory only.  As long as a properly certified mechanic has


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