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Serpentine Belt


Serpentine Belt is a ribbed belt that drives the engine's accessory. It usually drives an alternator, water pump, and air conditioner compressor. It is wrapped around several rollers and drive pulleys which gives its name.

  • It is a single continuous loop of a belt of reinforced rubber used to transmit power between two shafts.
  • The V- belt has a V-shaped crosssection that wedges into pulley grooves of matching width. Friction between the sides of the belt and the sides of the pulley grooves transmits the power. Power is not being transmitted through the bottom of the V - belt.
  • The ribbed or serpentine belt has a series of  V-shaped ridges that act as a series of small V- belt, The ribs or ridges wedges into matching grooves in the pulleys. Friction between the sides of the small ridges and grooves transmits the power.
  • Some older engines needed four to five V belts to drive   all then engine- driven devices 
  • The toothed belt drives the water pump through a sprocket instead of a pulley.