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Installation
Installation guideline designed to combat problems:
  1. Loosen Motor
    Check to make sure that the motor is off, a lock out tag out procedure should be in place to prevent accidentally motor start-ups. Loosen motor mounting bolts. Move motor until existing belt is slack and can be removed without prying.
    NEVER PRY OFF A BELT
  2. Remove Old Belt
    Remove old belt and check it for unusual wear. Excessive wear may indicate problems with the drive design or maintenance program.

  3. Select correct replacement belt
    If any of the pulleys have been replaced with a different number of teeth pulley than the center to center distance will have changed. Make sure that you are using the right length belt.
    NEVER FORCE ON A BELT THAT WILL JUST FIT, PRYING THE BELT ON WILL CRACK THE TENSILE CORD MEMBERS INSIDE THE BELT

    4.  

    Belt Handling

  4. Clean Pulleys
    Sprockets may be cleaned by wiping with a rag slightly dampened with a light, non-volatile solvent. Soaking or brushing the solvent on the belt is not advisable. Obviously, sanding or scraping the belt or pulley with a sharp object to remove grease or debris is not recommended. Belts must be dry before using on a drive.

  5. Inspect Pulley
    I    nspect pulley for unusual or excessive wear

  6. Proper Alignment
    Drive alignment is one of the most common causes of drive performance problems. Misaligned drives can show symptoms such as:

    7. High belt tracking forces

    Uneven belt tooth wear

    High noise levels

    Unee ven load distribution

    Tensile cord failur

    The two main types of drive misalignment are angular and parallel as illustrated in the below picture
Misalignments:

Parallel Misalignment
Parallel misalignment is where the driver and driven shafts are parallel but the driver and driven pulleys on these shafts lie in different planes.

Angular Misalignment
Angular misalignment is where the driver and driven shafts are not parallel. Resulting in uneven loading of the tensile cords. The tensile cords on the high tension side are often overloaded which may cause edge cord failure which would be transmitted across the width of the belt. This misalignment also results in high belt tracking forces which causes excessive belt edge wear,

Any degree of misalignment will result in some reduction of belt life, which is not accounted for in the normal drive design procedure. Misalignment of timing belt drives should be less than 1/4° degree or 1/16 per foot of linear distance.

A simple procedure to check misalignment (both parallel and angular) is by using a straightedge (ruler) to check alignment as the above illustration shows. The straightedge should be long enough to span the distance between the two outside edges of the pulley faces. Lay the ruler across the face of the two pulleys, if the two pulley faces are not even with the straightedge than you have parallel misalignment. Another possibility with using the straightedge method would be that one of the pulley faces would lay flush with the straightedge while the other pulley would have only one edge of the pulley face touching the straightedge. In this scenario an angular misalignment would be represented. This process should then be reversed using the opposite pulley as a starting point so that the total effect of the misalignment is taken into account. Remember to account for differences in the pulley edge thickness dimension and also the degree of bend on the pulley flanges.

Another procedure for checking for parallel