Hey guys, I am trying to get an old 1/2hp motor running. It’s missing the capacitor so I’m kinda at a loss where to start for a replacement. The cover to capacitor doesn’t have any sort of marking on it to help. All I have is the motor badge. Is there anyway to tell what size capacitor I should start with? Thanks!
Capacitor sizing for an old motor?
- Thread starter Jenkins
- Start date
marinusdees
Well-known member
Google it, or, better, find an electric motor repair shop, walk in and ask. They'll probably be able to sell you one. Values are pretty standard, depending on motr size.
I googled the motor and nothing really comes up for “Sunlight Motors” at all. Other than one vintage machinery page that has a few listed models but no real info.
I did just do a bunch of bonehead Googling to do some calculations and came up with a 400-480. Guess we will see where that leads.
Unfortunately the only independent motor repair shop local is ran by some really old guy who only services a few random customers. And that was a few years back. I’d be surprised if he’s still even doing it. He was in his mid 80s then. There is a chain style place but they service new stuff and focus on industry.
ALLFAST
Well-known member
Hello Jenkins,
You might try sending an email to [email protected] in Texas.
I recently consulted with him about my own unreadable capacitor specs ( 1 Hp single phase 1940s bench grinder) and he knew EXACTLY what would work ( given the different parameters and the “MFD” range).
The owner Hobie and he have been doing this for many years and they specialize in vintage motor repair and capacitors especially.
Mine was about 13.00 including shipping.
You might search for some threads with any similar motors with your data plate specs ( hp/amps/volts,etc) and see if those capacitor parameters are available. That will get you in the ballpark, as it isn’t super critical for a good working match.
Brandon more or less picked mine as an educated guess and it works like a charm ! It’s not rocket surgery.
Good luck and keep us appraised on your progress!
Stay safe,
Shawn
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ALLFAST
Well-known member
And as a side note, Mouser was of no help to me….their tech told me I’d need an electrical engineer to do a work up on my motor specs before he could help.
I found Caldwell by accident, spoke with Brandon for 12 minutes and he had it figured out with minimal effort!
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I've used this motor fact brochure for years when dealing with motors that had unreadable/missing nameplates. So I looked it up - and they have a section on caps - but no way to determine what size cap if IT is unreadable. So, that avenue is a bust. But I link the brochure here for anyone who's interested.
Well… I really stepped in it. Pulling the motor off its mounts and I turned my back to make sure the dog wasn’t licking grease. And it went crashing to the floor. Cracked the bell housing on me right at a bolt hole. But I didn’t let that stop me. I threw some wires on and the capacitor and it just hums, wont jump start with manual help either, actually it won’t turn when it’s buzzing. So I think I’ll pull it apart and clean the centrifugal switch. As for the cracked housing. Idk. I may try and JB weld it? I don’t know if it’ll take or not. But no harm in trying I guess. Pretty bummed about this one.
ALLFAST
Well-known member
Minor bummer. But your dog is worth more than the motor! JB Weld should be fine, and it is most like the capacitor ( make sure you have start vs run determined?) from my limited experience with similar situations.
Mintgrun
Well-known member
You could drill little holes on both sides of the crack and stitch it back together after JB weld. Chamfer the holes so the wire rolls over the edge. Brass wire would be nice to look at.
I recently learned that JB weld comes in both black and white. I used white to fix my kayak hull and learned just how off-white the boat is. I'm looking forward to getting some black. The dark grey original color works well for most things.
TOm
I recently learned that JB weld comes in both black and white. I used white to fix my kayak hull and learned just how off-white the boat is. I'm looking forward to getting some black. The dark grey original color works well for most things.
TOm