I am not sure about a second hand engine but would imagine you would have difficulty convincing the surveyor of its airworthiness without an overhaul or export CofA.
That one could be awfully tricky since sending your own engine to the USA means it is secondhand when it comes back here
But hey this is GA so there is a story behind that one too. Until some years ago, Continental allegedly didn't have JAR-145 approval for overhauls, although they did have it for new engines. So you could buy a new engine from them but bizzarely you could not send it back them them for an overhaul! So the story goes, anyway... it was reportedly OK on a privately used G-reg.
The problem with this stuff is verifying these stories. The refs I gave are relatively clear and if the CAA refused, one would get a solicitor on the job. CAA inspectors have been known to make up rules on the spot.
I think that if one is on the N-reg, and installs an engine suitable for an N-reg, and then transfers the whole plane to G, that would be OK because you start with an
FAA Export CofA done by an
FAA DAR, and that CofA obviously covers the entire plane. I haven't been able to verify this, either.... but if true it does defeat various scare stories about fitting parts to an N-reg which might later go onto G.
No wonder parts get fitted (to G-reg) without logbook entries. Makes life so much easier...
Edit: On reading AN14 again, I think Lister Noble ought to get an Export CofA with that engine, or ask the CAA before buying it. However, Sept 08 has passed and it's a different regime now anyway.