No announcement yet.

What is a Centrifugal switch & How do I lube?

  • Filter
  • Time
  • Show
Clear All
new posts

  • What is a Centrifugal switch & How do I lube?

    Thank you for the replies. First what is a centrifugal switch, and where is located on the motor? I would greatly appreciate any directions and or web sites that would help in the recommendation listed below by “Jim of all Tradesâ€‌

    Yep, sounds like the centrifugal switch is not kicking out. Probably from sitting too long in one spot. Take it apart and clean it, relube and go go go!

    Thank you all, Woody H

  • #2
    A centifugal switch is a set of fly wieghts that actuate a set of electrical contacts.These contacts are normally closed and feed power from the start capacitor to the start whinding which starts the motor over.Once the motor is up to speed the flywieghts flip out and the circiut to the start whinding is broken.

    The switch should be located inside the motor case behind the back(opposite the shaft end)endbell of the motor.

    You can use WD-40 to get the switch frred up and then use something like silicon spray lube for permanant lube.

    While you have it apart look at the contacts,they maybe dirty or burnt,if they are clean them using a fine file such as a flat needle or points file.

    If it is not the switch or contacts that are the problem,then check the start capacitor,if that is not the problem then the start whinding is burnt and it is time for a new motor or a re-whind.

    Use caution when handling or working on the centrifugal switch,they are many times made from bakalite or similar plastic and maybe very brittle.Also Graingers carries relacements to fit serveral different types motors.
    I just need one more tool,just one!


    • #3
      Hi Woody,
      If you are looking at the motor. The part you are looking to clean is inside the end where the shaft is not. Should be four long bolts holding the motor housing together. Be careful and make sure you have the motor disconnected from the line source, so you don't electricute yourself. Pay close and I mean close attention to how you take it apart so as to be able to put it together again. Now the part you will see when you get the endcap off will look like a donut with springloaded weights inside between two big washers with a wire attached to each. This is what needs cleaning of hardened lube and or rust and dust and grime. Use a good dialectric lube spray to relube,and you should be good to go. But again Pay attention and go slow on the teardown. Good luck you'll do fine.
      Jim, By the river enjoying life...


      • #4
        Thanks guys...


        • #5
          When ever I take apart a motor, the first thing I do is mark the end caps to motor joint with a marker or a small chissel across the seem. Them you are sure to get it back together right.


          • #6
            Hi Woody,

            I like to use my digital camera to take pictures of items I'm taking apart. It's alot better than my memory.



            • #7
              jim,you're a genius. .i'll file that for future reference.



              • #8
                BTW, whatever you do, do NOT get regular petroleum oils or grease on the contacts.

                It will burn and cause sticking or bad connections as the switch closes. That switch arcs as it opens, which carbonizes lube.

                There are contact greases, but in general dry is probably better if you don't have any.
                CNC machines only go through the motions.

                Ideas expressed may be mine, or from anyone else in the universe.
                Not responsible for clerical errors. Or those made by lay people either.
                Number formats and units may be chosen at random depending on what day it is.
                I reserve the right to use a number system with any integer base without prior notice.
                Generalizations are understood to be "often" true, but not true in every case.