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bill mullaley
07-11-2021, 8:25 AM
I bought this PM 66 that had been sitting for about 8 years in a garage. When I got it home I found a silver capacitor 97f9632 25 uf + 8 - 6%. It would not start the saw, it just hummed. I'm looking for capacitor size and whether it takes a start and run capacitor. There are three wires coming from the motor with one going through the centrifugal switch. The saw dates to 1987 (sn 876672038) and it took a bit to free it all up. I replaced the 3 belts as well. While changing the belts I found the motor pulley about 1/2-3/4" off the arbor pulley and had to adjust it lo align the bels. I guess someone had been tinkering with it. I was hoping someone has been down this rabbit hole and may have the info handy. Thanks, Bill

Bill Dufour
07-11-2021, 10:05 AM
25of. do you mean uf?
Do you mean it came with no caps at all? do you know how they should be wired in. voltage? 50 or 60 HZ etc.
Bill D.

https://inspectapedia.com/electric/Motor_Capacitor_Selection.php

bill mullaley
07-11-2021, 11:12 AM
Yes I meant uf. And no it only had the one. I can tell what wire is what by ohming them, but no if it takes 2 I'm not sure how it needs to b. It's 60hz. I was hoping someone with that machine could look and see what's on their motor. Thanks, Bill M.

Marc Fenneuff
07-11-2021, 11:14 AM
I brought home a gently-used 2001 PM66 last year, 3HP Baldor motor, ran fine when tested but after disassembly, cleanup and reassembly it wouldn’t run - the motor would only turn slowly (and loudly). Replaced the start and run capacitors (two separate trips) and no change. Wiring all looked fine. Finally I noticed an arc was occurring inside the starter when the start button was pressed (required removal of the starter cover - be careful). Since that didn’t seem safe/normal I looked a little closer and found the wire from one leg of the supply line wasn’t captured well by the screw terminal. Fixed that and I was good-to-go.

bill mullaley
07-11-2021, 11:31 AM
Any chance you still have the capacitor info? Mine only came with one and won't start the motor. Thanks, Bill M.

Carroll Courtney
07-11-2021, 11:44 AM
I could be wrong, but Start capacitor will be made of black plastic and run capacitor will me made of aluminum or silver as you describe

bill mullaley
07-11-2021, 11:58 AM
That's correct. I'm looking for the original sizes if possible.
Thanks, Bill M.

Mike Henderson
07-11-2021, 12:20 PM
Does the motor have a nameplate? Post a picture of the nameplate, plus the name of the manufacturer and the model number of the motor. With that someone can look up the motor specifications and perhaps even the wiring diagram.

Mike

bill mullaley
07-11-2021, 12:41 PM
460972
This is the nameplate for the motor, hope it helps. Thanks, Bill M.
Don't know why it's upside down...

Stan Coryell
07-11-2021, 12:45 PM
Do you have room for two capacitors? I would think you do.
Capacitor sizing is somewhat of a mystery to me. There is some math that will get you close. Luckily it's a Baldor, their technical service is very helpful. I don't work on a lot of FHP motors, but I think the capacitor you are using is way too small. I've never seen a capacitor start/run with a single capacitor. The run capacitor is normally oil filled. The one you have is probably a start cap for a residential A/C condenser. I've attached a diagram for a 5 HP motor. It'll at least help you sort out the three wires. Give Baldor a call Monday, they will have the correct single line, and capacitor specs for our motor.

bill mullaley
07-11-2021, 12:49 PM
Thanks Stan I'll do that. Bill M.

Stan Coryell
07-11-2021, 2:05 PM
No problem, sorry I couldn't be more helpful. I'd ring out the motor to make sure there aren't any obvious phase to phase or phase to ground shorts. I'd guess it was taken apart for a reason. The single line I posted should match your motor.

Bill Dufour
07-11-2021, 2:10 PM
Any chance the cap you have is two in one with three leads instead of two?
Bill D.

bill mullaley
07-11-2021, 3:17 PM
Pretty sure the motors good. Tried a cap I had but it was too high a uf and I shut it off right away. That’s why I’m looking for the original capacitors. Thanks Bill M.

bill mullaley
07-11-2021, 3:19 PM
No, it only has two terminals.
Bill M.

Mike Henderson
07-11-2021, 6:57 PM
Pretty sure the motors good. Tried a cap I had but it was too high a if and I shut it off right away. That’s why I’m looking for the original capacitors. Thanks Bill M.

Did it run when you did this test? If so, you know the motor will run, at least for a test. Also, if it started and ran up to speed, the cap would be taken out of the circuit by the centrifugal switch once it got up to speed.

Mike

Marc Fenneuff
07-11-2021, 8:19 PM
Any chance you still have the capacitor info? Mine only came with one and won't start the motor. Thanks, Bill M.

My start cap says 216-259μF and I don't see the run capacitor on the shelf with it. 2 terminals, Dayton 2MET8.

bill mullaley
07-12-2021, 6:19 AM
Thanks for looking Marc. I'm pretty sure the one I have is the run capacitor but will call Baldor or maybe Powermatic to be sure.
Bill M.

bill mullaley
07-12-2021, 6:25 AM
Yep it started and got up to speed but I wouldn't recommend reaching for a capacitor to disconnect it. 220 vac bites pretty hard! I'm going to make couple calls this morning and will post what they tell me.
Bill M.