Need Help with Vacuum Pump

Discussion in 'Shop Talk' started by debd0712, Jul 14, 2006.

  1. debd0712

    debd0712 Well-Known Member

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    I have a vacuum pump that I use for milking goats. We have had it just over a month - purchased used. The problem is that it will no longer start by itself when plugged in, but we can get it going by rapidly spinning the pulleys and it will remain running. When I plug it in it just hums and will trip the circuit breaker on the surge protector. I have kept the oil at the proper level. When you manually spin the pulley it seems like there is a point where the piston may be sticking. What should we look for and do to correct this? Thanks!

    Debbie
     
  2. danb98577

    danb98577 Well-Known Member

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    Is there a metal "can" screwed to the side of the motor or clamped on somehow? That is the start capacitor. Sure sounds like the culprit. Once in a while they are remotely placed near the motor and may be a rounded rectangular shape.
    Pull it off, write down wire color codes and where they attatch and head to a motor shop, or a heating/air conditioning shop. Shouldn't be any trouble to find a match, although the mounting screw locations may be off a bit. Luck-Dan
     

  3. Ross

    Ross Moderator Staff Member Supporter

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    Yup it may be the capacitor on the motor but be careful they store quite a jolt of electricity! Could be the start switch stuck open within the motor, or the start windings may be fried! Kind of depends what motor you have but that it will run if you pull the pulley means it the motor not your pump.
     
  4. moopups

    moopups In Remembrance

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    Ayep, look at the capacitor, there should be a weep hole on the end; if there is apparent moisture at or near that hole it is most likely bad. Don,t handle it more than necessary or smell it, if I remember correctly there are fluorocarbons present.
     
  5. debd0712

    debd0712 Well-Known Member

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    Thanks - we will check this out and hopefully find the problem. Have to wait until at least Monday when businesses are open.

    It has now started a new problem - when we get it started it sometimes does not sound right and has no pressure. If we turn it off and restart we usually get pressure, though it may take more than one try. Any ideas?

    Debbie
     
  6. danb98577

    danb98577 Well-Known Member

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    Is this a Surge unit by any chance? I left the dairy farm in 1968 so it has been a long time, but... I seem to remember a diaphragm/check valve assembly that would need attention at times. Might do you well to check with a large feed store and play twenty questions with them. Try to find the older folks working there-they generally are of more help in these areas. And take the manufacturer name, model, and other info with you. They can't help without this info. Luck-Dan
     
  7. Ross

    Ross Moderator Staff Member Supporter

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    Our Surge Alamo will sometimes not pull up the rubber flapper valve on the bottom of the vacuum reservoir quite right so it may need replacing. That or maybe your vac controller is acting up, or you have an automatic drain valve somewhere like on the reservoir that's malfunctioning.