BELT WEAR
Why would a new belt snap soon after installing it on your machine? First, check your machine. The problems could lie within! If there seems to be nothing wrong with your mower, check the following list of common belt failure problems to determine the belt problem and what may be the cause.

HAIRLINE CRACKS
If you notice that your belt has hairline cracks, your belt is dried out and old. These belts should not be used in this condition. You will just be borrowing trouble. Replace the belt with a new one.

LARGE CRACKS
Deep cracks can cause too much flexibility. This leads to heat build up and premature failure. These cracks can be caused by using the belt on a pulley that is too small. Notched belts are available for small diameter pulleys.

WORN, GOUGED, OR PEELING AWAY
If the belt is worn, gouged, or peeling away you may have a problem with your pulleys. Check the pulley grooves for roughness or if the pulley is bent or out of alignment. If nothing appears to be wrong then you could have a defective pulley.

BELTS SNAP WHILE IN USE
If a belt snaps it most likely means that there is excessive torque on the belt. This is usually caused by too high of RPMS when the belt is engaged. If this is not the case, check for any mechanical obstructions in the drive system.

BRITTLE BELTS
A new belt that has become brittle is a condition caused by extreme high temperatures. You should check the pulley bearings and other mechanical devices for cause of high friction.

SOFTENING
Oil and grease on a belt can cause the belt's rubber compounds to soften and separate from the reinforcing cords that hold the belt together. The belt will first slip, then fail altogether.

GLAZING
Glazing is caused by a belt that is slipping, resulting in overheating or poor performance. The more the belt slips, the more glazing will be built up on the surface of the belt. The more the belt is glazed, the more it will slip. If the glazing is light, tighten the belt.

These are just some of the common problems that occur with belts. J. Thomas belts are manufactured to exacting standards for outdoor power equipment. We recommend that you refer to your owner's manual for the proper installation instructions. Belts that are too tight or too loose can cause excessive wear, poor performance and damage to the equipment.