This lawn mower belt problem chart is a general guide and is not meant to be all inclusive. The cause listed below may not be your cause.
| Problem | Most Likely Cause |
Other Possible Cause |
| Cover is worn | • Backside idler |
• Belt rubs the guard |
| Belt swells, is soft | • Too much oil or grease |
— |
| Belt rides too high | • Wrong type of belt |
— |
| Hot Bearings | Too much oil or grease Poor bearing or shaft worn • Bearing too far from the pulley • Pulleys are damaged |
• Too much Tension |
| Wobbling Pulley | • Poor bearing or shaft worn • Pulley are damaged |
• Improper installation of pulley |
| Cracked underside | • Pulleys are damaged • Improper storage, stored too long |
• Too much heat • Backside idler |
| Cover splits | • Grooves of the pulley dirty (particles in them) |
• Insufficient belt on small pulley |
| Belts excessively vibrate | • Belts matched up wrong • Pulleys are damaged • Pulleys are misaligned • Too much tension • Not enough tension |
• Machine induced impulse |
| Belts bottom out | • Wrong type of belt • Belt has reached the end service life |
• Pulleys are damaged |
| Bushings are cracked | • Pulleys are damaged |
• Improper installation of pulley |
| Shaft bends | • Poor bearing or shaft worn • Bearing too far from pulley • Pulleys are damaged |
• Too much tension |
| Damaged tie band | • Pulleys are misaligned • Belt rubs the guard |
• Pulleys are damaged |
| Belt squeals or slips | • Too much oil or grease • Wrong type of belt • Stack is misplaced |
• Pulleys are damaged • Not enough tension |
| Belt comes off pulley | • Insufficient belt on small pulley • Too much moisture • Grooves of pulley dirty (particles in them) • Wrong type of belt • Not enough tension |
• Machine induced impule |
| Sidewall repeatedly word | • Harsh operating conditions • Too much oil or grease • Belts matched up wrong • Too much heat • Pulleys are misaligned • Not enough tension • Belts rub the guard • Stack is misplaced |
— |
| Repeated breakage | • Too much moisture • Grooves of pulley dirty (particles in them) • Machine induced impulse • Too much tension |
— |
Pros Tip: Always unplug your spark plug prior to working on your equipment.
We carry a large selection of Lawn Mower Belts. If you need help finding your Lawn Mower Parts, please complete the Lawn Mower Parts Request Form and we will be happy to assist you.
-Jack
