How to Diagnose and Repair a Capacitor Start Motor

How to diagnose and repair the capacitor on a capacitor start motor.

[Stallbeezy]

This was a great video. Helped me understand why my fan motor wasn't working. Thank you!

[gambit]

this video was what I was looking for. I am not experienced with electricity, and a fried said I can shock myself on the capacitors on the motor i want to fix (from my plate compactor).

I believe the "starter capacitor" is the problem on mine also, it hums, tries barely to spin or not and then breaker goes out after a few seconds.

Hope It goes well, and I remove them safely so I can (hopefully!) find and get new capacitor to try!

Thanks for the great video!

[atmian]

Thank you, very informative! Just pointing out that mFD means millifarad, which is 1000 times larger than one uF or microfarad, so 1 mF = 1000 uF.

[John-lz]

You deomonstrate the exact problem I have with my 7-ton Boss log splitter's electric motor not starting. Hums but doesn't start, quickly trips the breaker. I checked the capacitor and it's deformed and has no charge. Must have blown up after 8 years. A new one is $25 and a new electric motor is $211 so a Big Thank You!

[machinesCollectively]

Used your link to get that voltage tester, it'll be here tomorrow. ( baldor industrial 2 HP compressor motor ) thanks!

[alexgarza]

I love that I'm learning from a guy who seems to have lost part of his index finger.
Just the video I was looking for though. Thank you.

[glennfelpel]

Sure do appreciate you presenting this one. It always was a mystery to me about those capacitors on the motors. Never realized it was something we could find and change. By the where did you go to find the replacement. Possibly you did say but my computer is acting up and the sound didn't come through on parts of the video. Have a good weekend and stay cool.

[Tommy.]

I just came across this video and I think I will be able to fix my table saw. Thank you.

[tjofmaine]

Thank you for the video. Have a 6" joiner that has not been running and now I know why. Do you know if the supplied power to the unit will cause the capacitor to wear out faster. I'm wondering if the cable run to the shed and an extension cord to the joiner may be contributing to the failure? Thanks again for the video, I'm heading out to the shed to pull off the capacitor.

[kurthuck]

Nice video. At work a motor has same problem. They wanted to buy a new motor at $600.00! I told them let’s replace the capacitor first, only $55.00. Hope it works, I’ll earn some brownie points with owner if it does!🤣

[CPPY]

Hey, I just got given a Metabo Dust collector, and I plugged it in and nothing. I even changed the plug, thinking maybe a fuse. But same. When I turn it on, I don't even get a hum. There's nothing, would you know how I could get this running?

[MrBlackbutang]

Why is it that all the electricians I know are missing a portion of a digit? Absolutely Feckin Awesome!

[matthewrinehart]

My Corporation has switched over to WEG. The motors come in 230 v. and need to be re-configured to 115 v.. Unfortunately, the previous technician did not reconfigure the posts before installation, even worse, he tried to fix his mistake and now I have no idea what the factory setting was per the diagram before he monkeyed with the spade connectors. Any suggestions? If it will help, these motors are currently supplied for AMF 8290 pinsetters.

[JamesRousseaux]

Thank you so much. Extremely helpful. 😊 👍

[SwitchbackXThunter]

I have a Vevor 5hp 15amp motor and I just blew the capacitor on the right side as you're looking at the shaft. Is that the starter capacitor or the run capacitor? This is a new motor on an forging press. What causes them to blow? Thank you

[jackal]

Hi, where did you get the capacitor? I have a Hilka/Wolf bench grinder, I have to spin the wheel then it starts, Is there an equivalent capacitor I could use, The one on the grinder is blue, Two terminal connectors, it reads 5 uf +- 5%, we 350 .Ac 50 Hz .60 Hz .The grinder is 1/2 Hp 240 v 370W 50Hz 300 single phase.i don’t understand equivelant size capacitor I could use, I’ve looked on EBay but not one equivalent.Any advice would be grateful.Thanks

[peterhaan]

By centrifical clutch you should have said centrifical starting switch. Most elec motors use a starter winding along with the starting capacitor to assist starting the motor. Once up to speed a pair of centrifical weights swing out and remove the starting coil from the circuit. You can hear them click on motor spin up and again as the motor winds down.

[Xxxcappie]

Does the polarity of the capacitors matter the way you connected the wires?

[zachreyhelmberger]

I've got a single phase electric motor that is part of a standard single stage vacuum pump that will not spin. It has been running flawlessly for about a year on my Harvestright freeze dryer. The shaft spins freely by hand (after taking off the cover to the fan).It doesn't make any noise, or very little noise. It has two capacitors and I tested them with the multimeter and they are within spec and have greater than 1 meg of resistance after 5 to 10 seconds on the ohmmeter. When I plug it in and turn on the switch, sometimes it will spin a tiny bit, maybe 5 degrees or less and no hum. Otherwise it does not spin (or hum) at all. Both capacitors have about 120Vac across them when turned on. So I am kind of stumped. ANy ideas??

[DanfossDrivesAmerica]

1:12 (super loud hum) 15A AC GFCI Shorts Green Wire andThe White Wire Outlet Breaker: POP!