How Chain Saws Work

The Engine

Top view of the engine

With all of the cover plates removed, what you have is the naked engine, as seen in these two photos:

Bottom view of the engine

What you can see in these photos is that a chain saw is really just an engine with some cover plates bolted onto it, a handle to hold it, and a chain and bar to cut with. The engine is the main structural member that everything bolts onto!


In the photos above you can see all the major components:

  • The engine itself, visible mainly as the aluminum combustion chamber covered with cooling fins
  • The flywheel, which also contains the blower to cool the engine and the magnets for the magneto
  • The magneto
  • The air intake (which connects to the carb)
  • The spark plug
  • The spark arrestor/muffler
  • The centrifugal clutch
  • A small oil pump that lubricates the chain

These three videos are helpful in understanding the engine: