Author Topic: need help with my pump!  (Read 18391 times)

Offline ieezitin

  • Hero Member
  • *****
  • Posts: 662
need help with my pump!
« on: December 28, 2009, 07:18:07 PM »
Gentlemen.

My knowledge of electronics is very limited and I would like some advice on what is wrong with my pump. This is an industrial submersible pump and today I needed to pump out a field on my farm as we have had so much water I need to get rid of it or it will spoil my pasture.

The symptoms are this. Pump hums when power is applied and seems to be drawing so much power, the spindle starts then locks but if hit with a screwdriver the shaft takes off at full speed then rotates at full speed but the housing gets very hot then overloads the fuse which in turn shuts down. This is an oil enclosed pump and by the time the fuse goes the unit is too hot to touch.

The specs are this 3/4 hp, FLA 10.5, RPM3450, 60HTZ, 1 PH

All ideas are welcome.   I thank you in advance.  Anthony.











« Last Edit: December 28, 2009, 07:48:09 PM by ieezitin »
If you cant fix it, get another hobby.

Offline one_rod

  • Full Member
  • ***
  • Posts: 110
  • Country: gb
  • Chesterfield, Derbyshire.
Re: need help with my pump!
« Reply #1 on: December 28, 2009, 07:55:00 PM »
This sounds like a tight or seizing bearing. If you spin the rotor by hand with the power off does it feel rough or sound noisy? If so then there are two options.
If it is an expensive pump, it may be worth finding out how feasible it is to change the bearings. However, it's sometimes a horribly fiddly job on small rotors like that so if it is a cheap pump it may be better to simply replace the pump.

The only other possibility is a fault on the start capacitor or start winding on the stator.
Check the bearings first, if it's not them I will run you through the method for testing the electrics.

Best of luck.



one_rod.
"A season ticket for the one way ride..."

Offline ieezitin

  • Hero Member
  • *****
  • Posts: 662
Re: need help with my pump!
« Reply #2 on: December 28, 2009, 08:05:55 PM »
One rod.

Well. When the power is off I rotate the spindle and it feels slightly lumpy but smooth if that makes sense .Bearings seem ok at least the top set but not have dug in the bottom of the casting   This unit has not been ran for over a year that maybe of some interest.
« Last Edit: December 28, 2009, 08:36:22 PM by ieezitin »
If you cant fix it, get another hobby.

Offline 75Plus

  • Hero Member
  • *****
  • Posts: 624
  • Country: us
Re: need help with my pump!
« Reply #3 on: December 28, 2009, 10:12:55 PM »
In the picture of the capacitor the end appears to be slightly convex. This may just be the camera angle but if it is convex that is a pretty good indication of a bad capacitor. The end cap on new caps are perfectly flat.

Joe

Offline Darren

  • Madmodder Committee
  • Hero Member
  • *****
  • Posts: 3795
  • N/Wales
Re: need help with my pump!
« Reply #4 on: December 29, 2009, 07:34:34 AM »
My guess would be the starting capacitor as well. It's a cheap part so worth changing to see  :thumbup:

Have a look to see if the old one has any numbers on it. The voltage rating is important, you can replace with a higher voltage rating but not lower. The uf rating is not so critical, something close should do.
You will find it a distinct help… if you know and look as if you know what you are doing. (IRS training manual)

Offline tinkerer

  • Sr. Member
  • ****
  • Posts: 283
Re: need help with my pump!
« Reply #5 on: December 29, 2009, 10:00:38 AM »
When you spun it, was it in the same position it would be when pumping? My vote would be one of the bearings. If that is a run capacitor, the start winding could be staying engaged. If it is start capacitor, may not be strong enough to overcome binding bearings until banged around. Stand it on end and spin the rotor and see if it is not grinding.
Tink

The desire accomplished is sweet to the soul.
Prov 13:19

Offline ieezitin

  • Hero Member
  • *****
  • Posts: 662
Re: need help with my pump!
« Reply #6 on: December 29, 2009, 04:26:13 PM »
75 plus
Here is a better picture of the capacitor in a close up and it is rounded.

Tinkerer,

 I had it standing in the same position as it was to be worked. It turned on hummed a while then with me hitting the impeller it raced off but like I said lord did it get hot after a while, also my florescent lights went Bananas.

Darren

Got hold of the company for a price of a new capacitor today.

Now.  I have a multy meter any ideas to check if it is the capacitor or windings?

One more question!.. It seems to me that the stator and rotor are immersed in a thin oil maybe about 1 pint of oil why does it not short out?   Many thanks for all your help here... Anthony







If you cant fix it, get another hobby.

Offline 75Plus

  • Hero Member
  • *****
  • Posts: 624
  • Country: us
Re: need help with my pump!
« Reply #7 on: December 29, 2009, 05:20:04 PM »
The capacitor is definitely BAD. From the value it appears to be a run capacitor but it may be the reason the pump does not start properly. Replacing the capacitor should cure the heating problem. If there is a W.W. Grainger store anywhere near you they should have a replacement at a much better price than the pump maker.

As for the oil, these pumps run submerged in oil to preclude water from entering the housing. It is known as transformer oil and is dielectric (non conductive). A readily available substitute is common mineral oil sold as a laxative at most, if not all, drug stores. You will need to fill it to capacity and seal it well.

Let us know how you get on with it.

Joe
« Last Edit: December 29, 2009, 05:32:23 PM by 75Plus »

Offline ieezitin

  • Hero Member
  • *****
  • Posts: 662
Re: need help with my pump!
« Reply #8 on: December 29, 2009, 05:48:01 PM »
75 plus

I thank you for your advice and knowledge, it was Granger I phoned today for a replacement capacitor just waiting now for a price and delivery.

You have all helped a lot in my problem many thanks.  I will be posting the result of the new capacitor installation and to see if  it works.

I am going to post a thread on How Toos on electrical problems as I think there is a lot of mechanical guys like me out there who are not versed in simple electrical work and know how.

Many thanks Anthony.
If you cant fix it, get another hobby.

Offline Darren

  • Madmodder Committee
  • Hero Member
  • *****
  • Posts: 3795
  • N/Wales
Re: need help with my pump!
« Reply #9 on: December 30, 2009, 07:38:08 AM »
Hi Anthony,

I'd also say deff the cap, it's only a baby one and should not cost more that a few dollars.

The oil is an insulator, as previously stated it makes a good coolant in many electronic devices.

You are not realistically going to be able to test the cap at home without the correct equipment, it's a relativity complicated process.
Caps are so cheap even the electronics guys just swap suspected caps rather than test them.
« Last Edit: December 30, 2009, 07:40:27 AM by Darren »
You will find it a distinct help… if you know and look as if you know what you are doing. (IRS training manual)

Offline 75Plus

  • Hero Member
  • *****
  • Posts: 624
  • Country: us
Re: need help with my pump!
« Reply #10 on: December 30, 2009, 11:02:02 AM »
Been using this capacitor tester for over 20 years. Have yet to find a swollen capacitor that checked good.

Joe

Offline Darren

  • Madmodder Committee
  • Hero Member
  • *****
  • Posts: 3795
  • N/Wales
Re: need help with my pump!
« Reply #11 on: December 30, 2009, 11:09:01 AM »
Yes they used to be very expensive but I gather cap testers have come down a bit now?

How large a cap can it test up to, voltage and uf wise ?
You will find it a distinct help… if you know and look as if you know what you are doing. (IRS training manual)

Offline 75Plus

  • Hero Member
  • *****
  • Posts: 624
  • Country: us
Re: need help with my pump!
« Reply #12 on: December 30, 2009, 12:37:52 PM »

How large a cap can it test up to, voltage and uf wise ?

It will test from one pico farad (micro micro) to 20 milli farad (20 thousandth of a farad). It does not test for insulation breakdown as it only uses a 9 volt battery.

I bought it in the late 80's or early 90's. Think I paid about $40 US for it.

Joe

Offline Bluechip

  • Madmodder Committee
  • Hero Member
  • *****
  • Posts: 1513
  • Country: england
  • Derbyshire UK
Re: need help with my pump!
« Reply #13 on: December 30, 2009, 01:59:48 PM »
Darren

I use one of these wotsits, not a 'stress tester' for caps but very accurate. Handy little tool to have. Chuffed with it... I have/had some 10k .01% resistors from an old analogue computer, they all read OK, so I surmise the thing is about spot on. (That's right 0.01% 1:10,000  :)  )

http://www.test-meter.co.uk/products/lcr-meters/peak-atlas-lcr-meter-lcr40/

Got it some 3/4 yrs ago when Maplin mometarily lost a grip of their lifetime philosophy and sold 'em for less than Rapid/Farnell/CPC.

T'was £55 IIRC

Dave BC
I have a few modest talents. Knowing what I'm doing isn't one of them.

Offline Bernd

  • Madmodder Committee
  • Hero Member
  • *****
  • Posts: 3688
  • Country: us
  • 1915 C Cab
    • Kingstone Model Works
Re: need help with my pump!
« Reply #14 on: December 31, 2009, 02:12:27 PM »
I don't think there is anything wrong with the cap apperence wise. It looks like it was manufactured like that. The insulation may have broken down inside.

Bascially this breaks down to 2 possible problems electrical or mechanical. Since it's easier to replace the cap that would be first on my list. If that doesn't cure it, then I would think there is a binding in the bearings somewere when it gets warmed up.

Bernd
Route of the Black Diamonds

Offline tinkerer

  • Sr. Member
  • ****
  • Posts: 283
Re: need help with my pump!
« Reply #15 on: December 31, 2009, 05:05:01 PM »
Thinking some more, if that is a run capacitor, then there must be a start winding that should kick out when up to speed. If it isn't kicking out :zap:
Tink

The desire accomplished is sweet to the soul.
Prov 13:19

Offline crabsign69

  • Full Member
  • ***
  • Posts: 165
Re: need help with my pump!
« Reply #16 on: December 31, 2009, 05:07:41 PM »
i cant answer that one ....   but ya its broken  :D    i was bored  sorry    :) :headbang: :beer: :mmr:

Offline 75Plus

  • Hero Member
  • *****
  • Posts: 624
  • Country: us
Re: need help with my pump!
« Reply #17 on: January 12, 2010, 05:12:57 PM »
Hey Anthony,

Whats the status of your pump?    :scratch: :scratch:

Joe

Offline ieezitin

  • Hero Member
  • *****
  • Posts: 662
Re: need help with my pump!
« Reply #18 on: January 12, 2010, 05:32:55 PM »
Joe.

Funny you should mention this. I got in contact with Granger and the guy there gave me a hard time about me buying stuff from them as I do not have an account with these people. He asked what the I wanted and stuff took all the details then told me it will take about two days to get an answer on the time price and delivery for me.

I phoned today about it and they have no such information on record about me requesting that capacitor and again they gave me a hard time about me not having an account with them so screw erm!!.

So while we are at it any idea where I can get this part?

Thanks for thinking about me on this problem.    Anthony.
If you cant fix it, get another hobby.

Offline Bluechip

  • Madmodder Committee
  • Hero Member
  • *****
  • Posts: 1513
  • Country: england
  • Derbyshire UK
Re: need help with my pump!
« Reply #19 on: January 12, 2010, 05:49:07 PM »
Anthony

Motor start/run capacitors are not unusual parts.

Yours is 18uF 300VAC, if I remembered the label correctly.

A lot of FHP (over 1/4 HP) single phase motors have one.

Any electrical place that sells/repairs induction motors should have a good selection.
Only snag is, they may be different in physical size, making it a fiddle to get them installed sometimes.

Dave BC


« Last Edit: January 12, 2010, 06:19:56 PM by Bluechip »
I have a few modest talents. Knowing what I'm doing isn't one of them.

Offline 75Plus

  • Hero Member
  • *****
  • Posts: 624
  • Country: us
Re: need help with my pump!
« Reply #20 on: January 12, 2010, 10:16:56 PM »
Anthony,

You might check to see if there is a Johnstone Supply Co. in your area. They stock a couple that would work for you. They are 17.5 Mfd at 370 volts or 20 mfd at 370 volts. The higher voltage is a GOOD thing as they don't fail as often. You can also check this link. They sell a 2 pack for under $15. Not sure about the shipping though.

http://store.eurtonelectric.com/370volt.aspx

Hope this helps,

Joe

Offline ieezitin

  • Hero Member
  • *****
  • Posts: 662
Re: need help with my pump!
« Reply #21 on: January 13, 2010, 01:25:23 PM »
Joe.

Thank you for the link. I bought the two pack 20MFD370volt. They are en-rout to me as we speak. Must say the company you recommended was very helpful, polite and quick and was a pleasure doing business with them.

When they arrive I will install them and If I need help I will post. Either way I will post with the result.

Thanks    Anthony.
If you cant fix it, get another hobby.

Offline ieezitin

  • Hero Member
  • *****
  • Posts: 662
Re: need help with my pump!
« Reply #22 on: January 20, 2010, 08:31:53 PM »
Ok. So now I have my capacitors delivered to me now my question is I have a red and a yellow wire leading from my old capacitor what wire goes where? Can I get this configuration wrong? If you need pictures please let me know.

Many Thanks    Anthony…
If you cant fix it, get another hobby.

Offline tinkerer

  • Sr. Member
  • ****
  • Posts: 283
Re: need help with my pump!
« Reply #23 on: January 20, 2010, 08:43:18 PM »
There should be a small bead of solder on top next to the "identified" terminal, line voltage lead will go to that terminal. It has been a long time for me, so verify my info with someone more up to date. On second thought, the identified terminal is connected to the run terminal on the motor. Connecting it backwards can cause gases to build up and failure. of course, if the capacitor is in the start winding circuit, the same applies. Incorrectly and voltage can stay applied to the winding even when stopped.
« Last Edit: January 21, 2010, 02:28:12 AM by tinkerer »
Tink

The desire accomplished is sweet to the soul.
Prov 13:19

Offline 75Plus

  • Hero Member
  • *****
  • Posts: 624
  • Country: us
Re: need help with my pump!
« Reply #24 on: January 20, 2010, 09:32:58 PM »
Being an AC capacitor it makes no difference which wire goes where.

Joe