What Aircraft Buyers Need to Know About Engine Overhaul History

Aircraft buyers should be very cautious about engine overhaul history because this is one of the easiest places to make a very expensive mistake. A lot of buyers see a low number since major overhaul, maybe 300 hours or something similar, and immediately think that is a great thing. Sometimes it is, but sometimes that low number can actually be worse than a good engine with 1,500 hours on it.

The reason is simple: the number alone does not tell the story. What really matters is who did the overhaul, how it was done, what parts were used, and whether the documentation actually supports the work.

The Critical Role of the Overhaul Shop's Reputation

Not all shops are created equal. Even if a shop is FAA certified, that does not mean every overhaul coming out of that shop is the same quality. It also does not mean there are not bad actors in the market. And it does not mean things have not been done in the field that were poorly handled, undocumented, or outside the standard you would want on your own aircraft.

So when evaluating an engine overhaul, the first question to ask is: who did it?

Was it a dedicated engine shop with a strong reputation and years of history? Or was it some field overhaul done by an individual A&P where the records are unclear and the work may not have had the same level of process, tooling, oversight, or support? That does not mean every field overhaul is bad, but engines from dedicated engine shops that perform this work day in and day out are often preferred.

Another thing to look at is whether the overhaul shop is still around and whether it has real industry credibility. If the name on the logs is a shop with no website, no clear reputation, or a company that is not even in business anymore, that is a red flag. Support matters. Reputation matters. Longevity matters.

If you are not sure whether a shop is reputable, there is a simple way to learn. Call a few engine shops. Ask them where they get their overhaul engines from or who they would recommend if you were overhauling your engine. If multiple reputable people keep pointing to the same names, that tells you something. Then ask why. If their answer is all about quality, consistency, and support, that is a good sign. If the answer is mainly that one shop is cheaper, that should make you pause. When it comes to engine overhauls, quality matters a lot more than saving a few thousand dollars up front.

The Cost of a Questionable Overhaul

A questionable overhaul can significantly drag down an aircraft's value. If buyers see an engine overhaul from a shop with a weak reputation, that airplane will usually be worth less in the market, whether that shows up neatly in a pricing guide or not. Buyers know there is more risk there, and that risk affects what the airplane is worth.

We lived this ourselves with a Baron. We bought a Baron that had two engines with roughly 300 hours since major overhaul. At first glance, that sounded great. We thought we were getting an airplane with fresh engines and reduced engine exposure. Then about 50 hours later, one of the engines had a catastrophic failure.

We pulled the engines and sent them to our engine shop. What we found was that the company that had done the prior overhaul had a very poor reputation in the industry. There were parts that were out of tolerance, parts that should not have been used, and evidence of poor workmanship. In the end, both engines had to be overhauled.

That one issue cost us over $100,000 on top of a purchase we thought was a good deal.

That is exactly why buyers need to be cautious about terms like “fresh overhaul” or “low time since major overhaul.” Those terms do not automatically mean good. They only mean something if the overhaul was done by the right people, the right way.

Factory Overhauls and Age Considerations

Now, if you see a factory overhaul from Lycoming or Continental, that usually gives a lot more comfort because that is coming from the manufacturer itself. In many cases, that is the best-case scenario. That does not mean you stop paying attention entirely, but it usually means you do not have the same level of concern about the quality of the overhaul source.

The last thing buyers need to keep in mind is age. If an engine has 300 hours since major overhaul but that overhaul was done 10 years ago, that is a very different situation than 300 hours since major overhaul completed two years ago. At that point, you are not just evaluating the overhaul. You are evaluating time, inactivity, and all the same concerns that come with aircraft and engines that have sat too long.

So again, you need the full picture. At the end of the day, engine overhaul history is not just about hours. It is about trust, reputation, documentation, support, and how the engine has lived since the work was done. That is what buyers need to evaluate.