DRIVE MECHANISMS
7-25. The 2-stroke cycle engine drive mechanisms considered are the gear type, the chain type, or a
combination of both. Very few chain drives are used on 4-stroke cycle engines by the Navy. Therefore, only
the gear drives are discussed. The primary drive, which takes power from the crankshaft, is a gear assembly or
gear train. The arrangement of the gear train which forms the drive varies according to the engine