Maintenance Minute 1.5: The Engine Overhaul

Planned or not, an engine that has been declared "in need of overhaul" is a major event for everyone involved. The aircraft owner will be facing a significant expense and they will be unable to use their aircraft for an extended period of time. The maintenance shop will have the responsibility for a major repair involving several systems over many weeks to months. The overhaul facility will have to precisely overhaul an engine using a mix of old and new components without overlooking a single nut, washer, screw, or gasket.

In most cases, the aircraft owner assigns overall project management to the maintenance shop or a specific mechanic. The owner might be involved in some decisions with the maintenance shop acting as advisor, subject matter expert, and intermediary with vendors.

In all cases, it is essential for everyone to clearly understand the steps in the process and agree on who is responsible for the various outcomes. Easy, right?

Let's consider the decision about WHO will perform the overhaul. There are several overhaul facilities throughout the U.S. This is where you mechanic will provide a lot of input. They have undoubtedly worked with more than one and can provide some feedback.

A LOT of other questions and considerations will come up, such as:

• Shop crating and shipping or customer deliver?

• Core fee (if an exchange)? Terms and conditions of the exchange?

• New or overhauled accessories?

• When is a crank case beyond it's useful life?

• Aircraft storage while waiting for the engine?

• Is this a good time for other repairs and upgrades?

Based on data from recent projects, the cost of overhauling a typical 180hp normally aspirated Lycoming engine will range from $35,000 to $50,000 and take 18-24 weeks. This is just the overhaul and does not include removal, other repairs or upgrades, and installation.

Do not wait for your engine to reach TBO. Start the planning discussion with your shop now to reduce cost and downtime.