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Lawn Mower Belt Problem Reference Chart

Lawn Mower Belt Problem Reference Chart Posted in Lawn Mowers and Small Engines

Belts do so much to keep your equipment running smoothly. That's why it's important to keep them working in peak condition. Check them regularly to avoid serious problems.

The chart below shows some possible signs of belt problems and solutions. This chart can be used as a general guide and is not meant to be used as the sole source of information on belt problems.

PROBLEM MOST LIKELY CAUSE OTHER POSSIBLE CAUSES
Stack is misplaced Belt squeals or slips.
Sidewall repeatedly worn.
Cracked underside.
Belts rubs the guard Damaged tie band.
Sidewall repeatedly worn.
Cover is worn.
Backside idler Cover is worn. Cracked underside.
Improper storage, stored too long Cracked underside.
Sidewall repeatedly worn.
 
Not enough tension Belts excessively vibrate.
Belts comes off pulley.
Sidewall repeatedly worn.
Belts or squeals or slips.
Improper installation of pulley   Wobbling pulley.
Bushings are cracked.
Too much tension Belts excessively vibrate.
Repeated breakage.
Hot bearings.
Shaft bends.
Pulleys are misaligned Belts excessively vibrate.
Damaged tie band.
Sidewall repeatedly worn.
 
Pulleys are damaged Hot bearings.
Wobbling pulley.
Cracked underside.
Belts excessively vibrate.
Bushings are cracked.
Shaft bends.
Belts bottom out.
Damaged tie band.
Belt squeals or slips.
Too much heat Sidewall repeatedly worn. Cracked underside.
Bearing too far from pulley Hot bearings.
Shaft bends.
 
Poor bearing or shaft worn Hot bearings.
Wobbling pulley.
Shaft bends.
 
Belt has reached end of service life Belts bottomout.  
Belts matched up wrong Belts excessively vibrate.
Sidewall repeatedly worn.
 
Wrong type of belt Belt rides too high.
Belts bottom out.
Belts squeals or slips.
Belt comes off pulley.
 
Machine induced impulse Repeated breakage. Belts excessively vibrate.
Belt comes off pulley.
Too much oil or grease Belt swells, is soft.
Hot bearings.
Belt squeals or slips.
Sidewall repeatedly worn.
 
Harsh operating conditions Sidewall repeatedly worn.  
Grooves of pulley dirty (particles in them) Cracked underside.
Belt comes off pulley.
Repeated breakage.
 
Too much moisture Belt comes off pulley.
Repeated breakage.
 
Insufficient belt on small pulley Belt comes off pulley. Cover splits.


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