An overrunning alternator pulley can compensate for cyclic irregularities. These occur in all conventional internal combustion engines. After all, such engines do not have a continuous operating principle, but one that is divided into individual cycles.



For the belt, of course, these fluctuating speeds and torques are toxic. The solution: an overrunning alternator pulley.

This interrupts power transmission as soon as the speed of the alternator side exceeds that of the primary side. So the belt freewheels. The alternator shaft can then rotate faster than the belt pulley. It also enables the engine speed to be reduced quickly in the event of sudden load changes. That has a lot of advantages:

  • Smoother running
  • Less belt vibration
  • Less slip
  • Longer service life for belt and tensioner

Tip: The overrunning alternator pulley can be fitted more easily and safely using the TOOL BOX OAP.

The 12-piece tool kit is made in Germany using tough steel.
The socket head sizes have been carefully selected to ensure they are suitable for all common alternators. Further information is available in the Product Information Center (PIC).

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Published on: August 21, 2019

Filled Under: Belts, Technical Articles

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