Timing Belt Tooth Ratcheting

Proper tensioning cannot be stressed enough: too loose of tensioning will cause the timing belt to ratchet (tooth jumping), while too tight of tensioning will possibly cause damage to the bearings, shafts and other drive components besides dramatically reducing timing belt life. The correct timing belt tension is the lowest tension at which timing belts will transmit the required mechanical power and not ratchet teeth when the drive is under a full load.

Probable Cause:

  • Weak support structure or mounts

Corrective Action:

  • Redesign drive
  • Reinforce structure

Probable Cause:

  • Center to center distance fluctuates

Corrective Action:

  • Redesign drive

Probable Cause:

  • Excessive timing belt pulley wear

Corrective Action:

  • Replace timing belt pulley
  • Change timing belt pulley material

Probable Cause:

  • Fixed (non-adjustable) centers

Corrective Action:

  • Use inside idler

Probable Cause:

  • Excessive debris

Corrective Action:

  • Eliminate or control condition
  • Clean and protect drive

Probable Cause:

  • Excessive load

Corrective Action:

  • Check horsepower rating
  • Redesign drive

Probable Cause:

  • Sub-minimal timing belt pulley diameter

Corrective Action:

  • Use correct timing belt pulley diameter

Probable Cause:

  • Excessive low or high temperature (-30°F to 185°F)

Corrective Action:

  • Eliminate or control condition
  • Clean and protect drive
  • Reduce ambient drive temperature to 185°F maximum

Probable Cause:

  • Exposure to oil, solvents, harsh chemicals

Corrective Action:

  • Eliminate or control condition
  • Clean and protect drive

Probable Cause:

  • Timing belt, timing belt pulley or shafts running to hot

Corrective Action:

  • Check for conductive heat transfer from prime mover

Probable Cause:

  • Unusual timing belt degradation

Corrective Action:

  • Reduce ambient drive temperature to 185°F maximum
Technical timing belt calculatorcenter to center calculatorpower design
© Pfeifer Industries, LLC. - 2180 Corporate Lane - Suite 104 - Naperville, Illinois 60563-1639 USA
Telephone: (630) 596-9000 Fax: (630) 596-9002