Frog 249 BB model diesel engine
The FROG 249 BB is a model diesel engine that is often used in model aircraft. It’s a British-made engine, manufactured by IMA (a division of Lines Bros) from the mid-1950s. The engine features radial porting and twin ball bearing crankshaft.
This engine, a Frog 249 BB is new in original box with instructions. This dates to 1956 with serial number B243. From private collection.