It recently came to my attention that under FAA regulations, in order for the owner / operator / pilot to perform “Preventative Maintenance” that person MUST hold an FAA Airman’s Licence, issued under Part 61.
In other words, an EASA Licensed owner/pilot cannot exercise Preventative Maintenance activities as provided for under FAR Part 43, Appendix A, Paragraph C, unless he/she has an FAA Part 61 Licence.
So, although an EASA Licensed pilot / owner can indeed operate an FAA reg’d aircraft in his home country, he cannot touch it without a Part 61 “piggy-back”. .
Advisory Circular 43-12a: Preventive Maintenance:
Persons authorized to perform preventive maintenance. In addition to those persons listed in paragraph 4a of this AC, Section 43.3(g) authorizes the holder of a pilot certificate issued under Part 61 to perform preventive maintenance. Section 43.7 limits the privileges to persons holding at least a private pilot certificate and Section 43.5 prohibits operation of the aircraft unless approved for return to service. Further, pilots may only approve for return to service preventive maintenance which they themselves have accomplished.
Is replacing EGT, CHT or TIT probes preventive maintenance?
It is not explicitly listed as such in appendix A to part 43, but funny enough this is:
(29) Removing, checking, and replacing magnetic chip detectors.
pilot certificate issued under Part 61
You would need an FAA Chief Counsel’s view on whether a 61.75 piggyback meets that requirement, but I reckon it does. It is issued under Part 61 after all. That’s why you have the “61” in “61.75”.
Is replacing EGT, CHT or TIT probes preventive maintenance?
I am sure that is outside pilot privileges. It is IMHO within the scope of “avionics” work which is within the scope of “airframe” which is within the scope of an FAA A&P or someone working under his supervision.
That nobody can tell if you changed an EGT probe is a different matter 
That is why hangars where work is permitted are worth so much more.
A plain reading of the regulations says the holder of a pilot certificate issued under part 61 may perform preventive maintenance. Further it limits the privilege to holders of at least a private pilot certificate. So to me it is absolutely clear that the 61.75 pilot licence qualifies as the title indicates it is a private pilot certificate issued under part 61. Some relevant quotes from the regulations:
Sec. 61.75 Private pilot certificate issued on the basis of a foreign pilot license.
Sec. 43.3 Persons authorized to perform maintenance, preventive maintenance, rebuilding, and alterations.
(g) Except for holders of a sport pilot certificate, the holder of a pilot certificate issued under part 61 may perform preventive maintenance on any aircraft owned or operated by that pilot which is not used under part 121, 129, or 135 of this chapter.
Sec. 43.7 Persons authorized to approve aircraft, airframes, aircraft engines, propellers, appliances, or component parts for return to service after maintenance, preventive maintenance, rebuilding, or alteration.
(f) A person holding at least a private pilot certificate may approve an aircraft for return to service after performing preventive maintenance under the provisions of Sec. 43.3(g).
Aviathor wrote:
Is replacing EGT, CHT or TIT probes preventive maintenance?
No it is maintenance as It is not one of the specific listed items for preventive maintenance.
NCYankee wrote:
Is replacing EGT, CHT or TIT probes preventive maintenance?
Yes. It is not one of the specific listed items for preventive maintenance.
Sorry, now you confused me! Do you mean “Yes, even though it is not one of the specific listed items for preventive maintenance.” or “No, as it is not one of the specific listed items for preventive maintenance.”?
I edited it to remove the confusion.
NCYankee wrote:
No it is maintenance as It is not one of the specific listed items for preventive maintenance.
I kind of knew the answer to that, but thanks for confirming.
So you are allowed to replace chip detectors, but not temperature probes. I wonder whether this was intentional, or whether it is because airplanes with EGT and CHT probes on each cylinder were not commonplace when part 43 was written so nobody though of it.
Some airplanes have a CHT probe mounted on a spark plug in lieu of the gasket. So you are allowed to replace the spark plug, removing the CHT probe from the plug, and reinstalling the lot. But unscrewing a bayonette fitting to remove a CHT probe and undoing a spade connector, is a no-no.
A chip detector would just be a magnet.
Changing an EGT etc probe involves wiring. That is well beyond pilot privileges in FAA or EASA.
That a lot of people know how to do it is one thing, but I can see their thinking. It isn’t routine maintenance. I know they do fail from time to time but, on some engines, you change cylinders at a similar frequency, so why not make cylinder change a pilot privilege too?
A cylinder change (in terms of equipment and knowledge) is a bit more than unscrewing a CHT probe and putting a new one in! Lots of pilot PM privilege things (such as changing tyres or landing gear bungees) is a lot more involved than changing out a CHT probe.
