Auto Conversion Engines

[NCPilot]

I know that when it comes to certified aircraft engines, like Lycoming, Continental, etc. you can do basic maintenance yourself such as oil change, spark plug replacement etc. However, when it comes to more detail work or overhuals, you either has to send it to the company or have an A&P do the major works.

What is the rules concerning overhauls and major engine works when it comes to auto-conversion engines? Can I do the major work and Overhauls myself, or do those still need to be done by an A&P or the company that sells the engine?

[jaak]

If the aircraft is experimental amateur built, you can do almost anything you want yourself.

You still have to follow the operating limitations which are given by the FAA when the airworthiness certificate was issued.

[drseti]

I know that when it comes to certified aircraft engines, like Lycoming, Continental, etc. you can do basic maintenance yourself

For certified aircraft, the FARs allow for the owner/operator to perform specified items of preventive maintenance, but only if he or she has a Private Pilot license or above (Sport Pilots are excluded). The specific tasks permitted are listed explicitly in FAR Part 43, Appendix A. Anything not specifically listed must be performed by an A&P.

What is the rules concerning overhauls and major engine works when it comes to auto-conversion engines?

As a rule, auto engine conversions are used in aircraft that have a Special Airworthiness Certificate, typically in the Experimental-Amateur Built (E-AB) category. With E-AB, the rules are far more lenient than they are for certified aircraft (or even for LSAs). Pretty much anything goes, and mods and maintenance can be performed by a trained monkey (that's you! ) However, only the original builder can get a Repairman's Certificate to do the annual condition inspection. Otherwise, the annual must be signed off by an A&P. (The "owner/operator" privileges for preventive maintenance, as specified in Part 43 Appendix A, do not apply to experimentals.)