In common with other Le Rhône series engines, the 9J featured highly visible copperinduction pipes and used a single push-pull rod to operate its two overhead valves. The main visual difference between the 9J and the earlier, less powerful Le Rhône 9C engine is that the copper intake manifold tubing (with round section lower ends) on the 110 hp 9J is attached to the crankcase behind the cylinders, whereas on the 9C (80 hp) the intake manifolds (with rectangular lower ends) are fully visible from the front.
A Bristol M.1 replica, owned and operated by the Shuttleworth Collection remains airworthy and is powered by a Le Rhône 9J engine. The collection's airworthy Avro 504 is also powered by a 110 hp Le Rhône rotary engine. The reproduction Avro 504 at Old Rhinebeck Aerodrome has also flown with an original Le Rhone 9J powerplant, as was Cole Palen's first reproduction Fokker Dr.I monoplane (now retired) for Old Rhinebeck's airshows in the 1960s, bearing American registration N3221.