Getting the Most from a Belt

With the mowing season now well under way, mower parts that were marginal last year may start to fail. The belt that seemed “good enough” at the end of last season may need attention or replacement when you start another run at the jungle in your yard. All riding mowers and some self-propelled walk-behinds have a belt – probably the weakest link on a mower.

Here are a few suggestions on getting the most from a belt and how to determine the cause of belt failure.

To help a belt live longer:

  • Don’t engage it at full throttle or in tall grass.
  • Try to keep foreign material from building up around sheaves and in the belt pathway.
  • DO NOT use belt dressing. (Most belt dressings use a petroleum base that deteriorates rubber compounds.)
  • When installing a new belt, do not “pry” the new belt on. This can damage the cords and may cause premature failure.

Try to determine what caused belt failure. Too little tension may cause slipping and result in glazed or shiny belt sides. An incorrect belt choice may cause this condition as well. Too much tension is also detrimental.

A ragged edge generally means that the belt has come in contact with a foreign object, debris in or around the area that the belt travels, or is rubbing on a shield or belt guide.

Misalignment or lack of tension may also cause a belt to “flop” or become disengaged. If the belt comes off the track several times, the cord may become permanently damaged and fail to remain in alignment.

One last note: For proper pulley alignment, follow the general rule of thumb allowing 1/16 inch variance for every 12 inches of belt run.