Peter wrote:
unless an independent engine shop is outright crooked, they will not reassemble an engine as “overhauled” which is outside the manufacturer dimensions and other guidelines, and the shop has an incentive to reveal all under-spec parts it finds because they make the trade margin on replacing them
I don’t think there are manufacturer dimensions for overhaul, there are instead limit dimensions and guidelines for ‘serviceable’ and ‘new’. Overhaul means take apart, inspect and put back together, as defined in FAA terminology. The owner’s opportunity to operate independently in maintaining a serviceable engine (which means exactly that) is an asset which is eliminated when a factory TBR program is forced on the owner by the manufacturer. That drives up costs in conjunction with the TBR program also eliminating competition between engine parts suppliers.
The shop doing aircraft engine work can be any A&P mechanic, even one on working on his own engine, and whether it’s that or an engine overhaul facility, the best and most proper incentive is to serve the owner of the engine and his needs. I don’t think (for example) that throwing away expensive sole-sourced parts that may be barely outside new limits after 2000 hrs serves the paying customer.
