TROUBLESHOOTING BELT NOISES ON MULTI-RIB DRIVE APPLICATIONS
Understanding and distinguishing the different types of belt noises are critical in order to solve the actual root cause of the noise
Noises emitted from the belt in a drive system have been characterized as squeal, chirp, squeak, rumble, whine, and tick, and actually are noises with different system causes. If the proper noise can be identified, then a person can more easily determine and correct the root cause, thus eliminating the noise.
The two most common noises heard from a drive system are:
1) Chirp Noise
2) Squeal Noise.
Chirp noise is a series of sharp, intermittent noises that are caused by misalignments between consecutive pulleys in a drive. Squeal noise is typically a consistent, high pitched noise that is the direct cause of relative slip between the belt and pulleys.
In order to determine if the noise is a chirp noise or a squeal noise, one method is to spray the rib side of the belt with water. If the noise diminishes or is temporarily eliminated, but then returns after the ribs dry out, then the noise is characterized as chirp, and thus is caused by a pulley misalignment. Also, if the noise is reduced as the engine speed is increased, then more than likely the noise is a chirp noise, which is caused by an alignment issue of the pulleys. If when sprayed with water the belt actually increases in noise, or the noise increases with rapid accels/higher engine speeds, then this typically means that a belt is slipping, and thus would be characterized as a squeal noise.