The DC gearmotor that we use has a life of 2,000 operating hours (not simply power-on hours) and then it needs to be replaced. The brushes eventually wear out inside the motor and it gradually loses torque (power).

The user will see signs of the belt slipping on the ball winder pulley. The motor has less torque as it ages and is seemingly unable to turn the ball winder or pull yarn from a swift.

When this happens, you replace the motor with  a spare from NKK. The user can easily replace the motor in the field.

Note! Other conditions can also appear as a worn out motor condition, however!

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Stretched drive belt - the belt will stretch in response to increased load on the motor. When the belt stretches, then it starts to slip on the pulley when it sees just a little drag from the system.

Plus, the flange o-ring on the ball winder can be too tight against the pointy shaft on the ball winder and this will create tremendous drag on the motor. This o-ring may also have cracks in it - replace it if it does.

Plus the ball winder may be full of fiber debris.

So, the user should do the following in this order to investigate the cause of their slow motor or lack of power condition:

  1. Make sure the flange oring on the ball winder is not pressing too tightly against the shaft. See our video on youtube on making this adjustment O-ring Adjustment 2 Instructional video
  2. Next, the user should inspect the interior of the ball winder for fiber debris buildup. See this video Clean your ball winder video
  3. Inspect the o-ring for cracks or other damage and replace if necessary
  4. Install a new belt between the motor and the ball winder (if you do this before you check the other areas, the winder may work fine but the root cause of the problem is still there possibly, so do not depend solely on replacing the belt to solve the real problem).
  5. Check the original installation date for the Power Base and determine how long it has been in use. Calculate how many hours of use you subjected it to during that period. If it is over 1,500 hours then if the other factors are OK, then the motor may indeed be wearing out. Get a replacement motor from NKK and install it easily yourself. See below for details.

    Note - the motor is rarely the source of the problem. It is usually a dirty ball winder or a stretched belt or a flange drive oring that is too tight.

    How to calculate how many hours you have on the motor

    Determine how many hours per day you run the motor (on average). How many days per month do you work with the ball winder. Multiply the hours per day x the number of days per month and this will give you the number of horuis oer month that you use the ball winder.

    Divide that number into 2,000

    That will give you the number of months that you can run the unit from the day you first got it until the motor needs to be replaced (on average).


    • 2 hrs per day
    • 25 days per month
    • 2 x 25 = 50 hrs per month
    • 2,000/50 = 40 months (3 years 4 months)

    If you use the motor drive professionally, we recommend getting a spare motor ahead of time at 1400 -1600 hrs (28 - 32 months) so if the motor fails you will have a backup available.

    Notice - some motors last longer and some last less time. They are only covered by the NKK 1 year warranty for the first year. Under normal usage patterns, they never fail during the first year.

    Final note, during a typical motor's life, the motor will wind 15 to 20 Million yards of yarn for the user. That is like winding yarn into balls that was stretched 1/2 way around the Earth (11,500 miles). So when it finally does fail, please don't yell at the motor, give it a pat on the motor housing and tell it "good job!" Then go to your phone or computer and cheerfully order another motor from NKK!