Riding Lawn Mower Deck Belt Keeps Breaking

Are you mowing along and your deck belt starts squealing or smoking and then snap! Yeah….you just broke another one.

But why does this keep happening? In a lot of cases, it is the deck pulleys that are freezing up and causing the belt to slip. When they slip, the rubber burns off of them and before you know it, they break. There could also be some misalignment in the pulleys that is causing the problem or the belt could be routed incorrectly.

Remove the deck to check the pulleys for ease of rotation, proper alignment of the belt and proper routing. Do you have the correct belt for the riding lawn mower? Is it a good quality belt such as an OEM and not an aftermarket one? Some aftermarket belts are made from inferior materials and are not the exact same size as the original OEM one. Even a fraction of an inch can make a difference on some models.

If everything looks good, check the PTO pulley and make sure that it looks in good condition. Check the deck belt guides on the frame and near the PTO. They can come loose and cause the belt to rub. Are you installing the belt correctly around these guides?

If everything checks out and you still have a problem, visit our Locations page for a riding lawn mower repair shop near you.