The Shuttle engines operate on hydrogen which burns very cleanly. RP-1 will leave the engine dirty with coking, so they definitely need to clean re-assemble each engine.<p>On the other hand, the solid boosters of the Space Shuttle were severely damaged by the impact and corrosion of the sea water, after &quot;recovery&quot; they were essentially a source of parts for new boosters.<p>Overall, I really hope they can improve re-usability above what the Space Shuttle achieved.