New or Newly Overhauled Aircraft Cylinders

Breaking in new or overhauled aircraft cylinders is critical; and it should occur for everything from installing an entirely new, rebuilt or overhauled engine, to a top overhaul, to the simplest replacement or overhaul of single cylinders. Without it, aircraft owners could face costly consequences resulting from things like excessive oil consumption, glazing and unnecessary, untimely component wear.

Suggested Steps to Take During Aircraft Cylinder Break-In

To ensure maximum longevity and performance after an overhaul or aircraft cylinder replacement, break-in procedures should include:

• Avoiding extended low-power operation (including prolonged taxiing and idling, so you want to limit ground runs as much as possible) to prevent glazing, which is the unwelcome build-up of carbon on cylinder walls.

• Utilizing high power operation within safe pressure limits, as necessary ring expansion requires the pressure generated by that power.

• Using mineral oil without anti-wear or frictional modifiers, as synthetic oils can interfere with ring seating. Please note that direct metal to metal interaction of piston rings and cylinder walls is required for proper seating, but should not extend past the aircraft cylinder break-in process.

• Operating within proper temperature limits is also essential for breaking in aircraft cylinders. So, using temperature-sensing devices on each new or overhauled cylinder during ground runs is good practice, as is maintaining limits between 300 and 400 degrees during ground runs, below 420 degrees during aircraft cylinder break-in for Continental engines and below 440 degrees for Lycoming engines.

• Then keep detailed logs of temperatures as well as your oil consumption.

• Obviously, you will want to avoid any flight training during the aircraft cylinder break-in process as well.

How Long Does It Take to Break-In Aircraft Cylinders?

Proper aircraft cylinder break-in procedures over the short-term result in the best long-term gain; as the break-in period doesn’t last long, but doing it right will result in optimal aircraft engine performance longevity. 

Most ring seating occurs within the initial five to ten hours of the aircraft cylinder break-in process, but stabilization of oil consumption could last approximately 50 or more flight hours. The flight break-in process is complete once oil consumption becomes stable.

Also keep in mind that not all cylinders are alike and aircraft cylinder break-in timing depends largely on coating type. For instance, while low-friction nickel-carbide aircraft cylinders tend to break-in quickly with oil consumption remaining low throughout the process, channel chrome aircraft cylinders take longer with higher oil consumption. There are also steel aircraft cylinders which are more likely to take approximately ten hours.

An Oil Change Should Immediately Follow Aircraft Cylinder Break-In

Something else that you should be hyper aware of about the process is that oil contamination is a common occurrence during aircraft cylinder break-in. Consequently, an oil and oil filter change to remove any metal particles caused by rings and cylinder wall wear is essential immediately after the aircraft cylinder break-in process is complete. Immediately really does mean very quickly, so don’t wait more than ten hours.

Plus, it is important to follow your particular manufacturer’s recommendations. If all of this seems daunting or you have any questions, follow the professional advice of a trusted aircraft cylinder mechanic, such as Moore Performance Products…

A Trusted Aircraft Cylinder Specialist for Over 30 years

Family-owned and operated since 1995, Moore Performance Products has spent the last three decades specializing in aircraft cylinder overhauls and is dedicated to exceptional service and the highest quality results. 

Additionally, Moore Performance Products is not only an experienced aircraft service provider specializing in aircraft cylinder overhauls and repairs for local pilots and aircraft owners, the Moore aircraft cylinder experts are trusted to provide a variety of overhaul services nationwide and overseas for the aircraft and aerospace industries. Moore Performance Products is also an FAA-certified repair station as well as FAA-certified in welding. 

Moore Performance Products is conveniently located at 132 W. Park Avenue, Building 1 in Edgewater Florida and can be reached by phone by calling 386-409-7501 or 888-409-7555 anytime between 9 a.m. and 5 p.m. Monday through Friday.