Second Stage Drive Belt Tension Adjustment

About

This procedure provides instruction to adjust the Second Stage Drive Belt tension.

A Two-Stage Input Drive system uses a first-stage drive belt and second-stage drive belt system to connect the input drive assembly pulley to the generator/brake assembly pulley. Always adjust the first stage drive belt first and then the second stage drive belt.

IMPORTANT:  Adjust the first stage drive belt tension prior to adjusting the second stage drive belt tension.

Specifications

System Component Specification
Second Stage Belt Drive Tension - New(1) 110-120 lbs (50- 54.4 kgs)
Second Stage Belt Drive Tension - Used(1) 92 - 105 lbs (43 - 47.6 kgs)
Drive Component Assy Carriage Bolts 180 in-lbs (20.3 Nm)
(1)  New belt tension applies to new belt first time installations. Used belt tension applies to reinstalling an existing belt or when re-tensioning an existing used belt.

Procedure

Review entire procedure before starting.

  1. Remove the drive disk access cover, see Drive Access Panel Replacement.
  2. Remove the left Drive Disk cove, see Drive Disk Covers Replacement.
  3. Measure and verify that the first stage drive belt tension is within specification, see First Stage Drive Belt Tension Adjustment. If the belt tension is not within specification, retention the belt.
IMPORTANT:  Adjust the first stage drive belt tension prior to adjusting the second stage drive belt tension.
  1. Use a 1/2" socket to loosen the two Generator/Brake Assembly bolt nuts (left side) just enough to allow assembly movement. Do not remove the carriage bolt nuts.

CAUTION: Make sure that the two Generator/Brake Assembly carriage bolts are loosened before adjusting the second stage belt tensioner. The tensioner hardware can be damaged and the belt cannot be tensioned if the Generator/Brake Assembly are not loosened.

  1. Place the belt tension gauge onto the Second Stage Drive Belt midway between the Generator/Brake pulley and larger Step-up Assembly pulley and measure the tension. Record the measured belt tension.
  2. Compare the measured belt tension to the second stage drive belt tension specification.
  3. System Component Specification
    Second Stage Belt Drive Tension - New 110-120 lbs (50- 54.4 kgs)
    Second Stage Belt Drive Tension - Used 92 - 105 lbs (43 - 47.6 kgs)
    Note:  New belt tension applies to new belt first time installations. Used belt tension applies to reinstalling an existing belt or re-tensioning an existing used belt.

  4. If the tension is not within the specified Limits, do the following tension adjustment steps to bring the tension within specification:
    1. Remove the belt tension gauge.
    2. IMPORTANT:  The belt tension gauge must be removed while making tension adjustments or the measurement will be invalid.

    3. Make a small incremental adjustment to the 1/2" Second Stage Belt Tensioner bolt as needed (loosen or tighten) to bring the belt tension into specification.
    4. Note: Belt tension adjustment is an iterative process, only make small tension changes per adjustment. Be careful to NOT over tension the belt, which could result in damaging the belt or pulley hardware.

    5. Then use the crank to rotate the input pulley a couple of rotations to seat the belt and remeasure the belt tension.
    6. If the belt tension is not within specification, repeat the tension adjustment process until the belt tension is correctly tensioned.
  1. Use a 1/2" socket to fully tighten the two Generator/ Eddy Brake Assembly carriage bolts (left side), torque bolts to 180 in-lbs (20.3 Nm).
  2. Reinstall the left Drive Disk cove, see Drive Disk Covers Replacement.
  3. Reinstall the Drive Access Panel, see Drive Access Panel Replacement.
  4. Verify machine operation and return to service.

 

See Also

First Stage Drive Belt Tension Adjustment

 

 

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