TS motor issues

[Britt Lifsey]

I have a 10" belt drive Craftsman TS I bought new in late 80's. I had not used it for several years until daughter and I built her an entertainment center and book shelves for college last year. As I posted in a similar thread here, it started being very slow to start and would hum/grind before spinning up to full RPMs or sometimes not start at all (tripping breaker if I waited too long). I took motor apart, cleaned it up, re-greased bearing, etc. and it has worked fine with moderate usage until yesterday :( It started acting same as last year.

I don't have analog multimeter to test start capacitor. I have done following for troubleshooting this issue:
1 - started TS with belt removed. Has same issue although not as "pronounced".
2 - swapped capacitor with my HF 2HP DC. The DC is a 400mfd/110VAC. The TS does start a little better but would sometimes make the hum/grind noise...just maybe not as long. The DC started up just fine with capacitor from TS.
3 - swapped capacitor from a Craftsman 1/2HP lathe. The lathe capacitor is 230-280mfd/110VAC. Almost identical results to swapping with DC. TS starts a little better but still not like it should. Lathe motor (no stock in lather) starts just fine with TS capacitor.
4 - I do hear the "click" of centrifugal switch disconnecting when motor is winding down after turning off.

For now, I've left the lathe and TS capacitors swapped since I really don't use lathe (bought several years ago hoping to try turning but haven't really gotten into it). Since the hum/grind didn't go away with 2 known capacitors I'm afraid TS motor might have an internal problem (start windings, etc).

Any thoughts or other words of wisdom to resolved? I'm not sure I want to put $200+ in a new motor for a 23 year old TS.

Thanks!!!

[Ken Fitzgerald]

Britt,

When you had the motor apart, did the contacts on the centrifugal switch appear okay?

Also.....check that switch now that this is happening. They have a way of getting sawdust in there. They may spin open but the sawdust keeps the contacts from making an electrical contact. Wood is an insulator when dry.

[John Hart]

Britt...Ken has a good idea there. It sure makes sense. Sorta like a resistive short causing a slow start-up. I'm also concerned about your description of "grinding".
Is it possible that when you put the motor back together after greasing the bearings, that you lost your end-play on the rotor?

Sometimes, if the assembly is too tight, there is added pressure on the axial dimension of the rotor. maybe you could disassemble it and inspect the rotor for signs of rubbing.

[Britt Lifsey]

Left the points part out :cool: When closed they are registering "infinity" on my digital multimeter and, of course, 0 when I open them with my finger.

The is still a fair amount of end play. The arbor looked clean/shiny where bearings contact it. It turns freehand very easy.

Thanks for ideas! A distance cousin on my mom's side used to run a motor shop in a nearby town but he retired several years ago. I might give him a call...maybe he still has tools/equipment at home and can check it out for me.

[Dave Beauchesne]

Left the points part out :cool: When closed they are registering "infinity" on my digital multimeter and, of course, 0 when I open them with my finger.

The is still a fair amount of end play. The arbor looked clean/shiny where bearings contact it. It turns freehand very easy.

Thanks for ideas! A distance cousin on my mom's side used to run a motor shop in a nearby town but he retired several years ago. I might give him a call...maybe he still has tools/equipment at home and can check it out for me.

Britt:

You have it backwards - the contacts should read ' zero ' when closed, and infinity when open.

As for the retired motor guy; he will have it figured out in a heartbeat i would guess.

Dave Beauchesne

[Britt Lifsey]

You have it backwards - the contacts should read ' zero ' when closed, and infinity when open.
Oops :o :o :o that's what it I meant.

[Lee Schierer]

I have a craftsman saw of nearly the same vintage. On each end of the motor you should see a small yellow plug. These plugs should be pulled about every 6 months and a few drops of oil put in. The bearings in your motor are most likely oilite bushings and if they have not been oiled, they could easily be worn out. Worn bushings will allow the armature to get out of line with the magnetic field enough that the motor will not start correctly. Do not use grease on the motor shaft.

Also check the belt tension to insure the motor is free to pivot. Craftsman saws use the weight of the motor to achieve belt tension and the motor must be free to pivot.

[Britt Lifsey]

Thanks Lee. Until I tore apart motor last year I was not aware of the oil caps (sadly so much dust had collected in that area they could not be seen). Bushing could be worn from long term use without oiling. I'm afraid years of neglect on my part is the culprit :(

I replace belt last year also and it is under tension. The motor pivots freely and keeps belt tight. I have the starting problems even with the belt removed and motor just spinning the pulley.

[Britt Lifsey]

John,
Grinding is probably a bad choice for description. It is a hum like sound but very loud...much more so than what I've heard from electric motors.

[John Hart]

John,
Grinding is probably a bad choice for description. It is a hum like sound but very loud...much more so than what I've heard from electric motors.

Ah....that IS different!. What you are describing is the loud hum of opposing magnetic fields and high current. It it the condition that normally exists at start-up (normally for about 250 milliseconds). However...you are describing it as something that goes on for many seconds.

Ya know....it is very possible that the Run Capacitor is not completely bad...but is going bad.

A bad run capacitor would give the symptom of sitting there humming until the overload trips....but since that motor doesn't have a breaker...plus, it's not completely bad.......hmmmm

sorry...just thinking and typing out loud. :rolleyes:

[Dave Lash]

Many motors use oilite bushings which are impregnated with oil when manufactured. In my experience once the oil in the bushing is used up, the motor will start or run slowly, or not start at all. Oiling the bushings will usually return the motor to normal operation, but the bushings will have to be oiled reguarly as there is not any impregnated oil left in the bushing and the oil you added will not last that long.

[Rod Sheridan]

Most sleve bearing motors have a wick type reservoir that holds the lubricating oil.

If you oil the wick enough to re-saturate it, it will re-establish the original oiling intervals.

Regards, Rod.

[John Hart]

oh! another thought....Since the saw has just been sittin' doin' nuthin' for a while...maybe the connectors on the run capacitor are corroded up underneath the foldovers of the connector.

Still thinking and typing out loud.:rolleyes:

[Don Jarvie]

As other have eluded to it could be the contacts that need to be cleaned.

You may want to take the motor apart again and clean it out with compressed air. Clean tha oil cap area, etc. Really give it a good clean up.

Here is a link from OWWM.com regarding the cleaning of the contacts that may be helpful. They may not be as bad as the link shows but a little 600 grit sand paper on the contacts may be all that is needed.

http://wiki.owwm.com/Baldor%20Motor%20Repair.ashx

Also make sure the wiring is correct when you put it back together. If it can be wired for 110/220, just 1 wire miswired will allow the motor to run but not well at all.

Good luck

[Britt Lifsey]

Thanks for all the input/help! I'll do some more piddling with it after work this evening and report back.

[David Cefai]

Your capacitor swapping test may not be completely valid. You need to swap with a reasonably similar value cap. You didn't say what the value of the capacitor was.

[Britt Lifsey]

Cleaned the points with metal nail file and used Q-tip and cleaned with alcohol. It might be starting better...but not much. Could just be wishful thinking.

I'm starting to think the bearings/bushing are worn from several years of use without oiling and then letting saw sit for a few years with only very, very, very occasional use.

Haven't had chance to ask my mom about the cousin.

[Britt Lifsey]

My contacts didn't look near that bad.

[Britt Lifsey]

As I mentioned below, I'm starting to wonder if the bearings/bushing might be worn out. Would excessive play allow the shaft to misalign and cause this?

This motor only has start capacitor.

[Britt Lifsey]

I can't read the sticker on capacitor :(

My thoughts were the TS motor symptoms didn't change with either "size" capacitor but the other motors both worked perfect with the capacitor from TS. Would that not indicate the capacitor is OK?

[Don Jarvie]

While you have the motor apart get a wire brush like you use to clean copper pipe and see if you can clean the inside of the bushings, The take each end of the rotor and clean the shaft where it would sit in the bushing. The put some paste was on the rotor ends and see if that helps.

Cleaning out the gunk and surface rust may help.

[Tom Welch]

I am wih David, sounds like it could be your starting cap. I had the exact same problem with the motor on my shaper, same humming, and not coming up to speed. I also tripped a breaker, I replaced the starting cap and it now runs like a champ. I think your over thinking this here. Your cap really needs to be the correct size etc for the motor, swapping caps from other mtrs is really not good troubleshooting unless it is the exact same mtr. Over the years most of my problems with motors is the starting cap.

[Britt Lifsey]

I think your over thinking this here.
Probably right on that. But, it keeps me off the streets and out of the pool halls ;)

I think I'll take the capacitor into the house under better light and maybe use wife's craft magnifying glass to see if I can make out the mfd for it. They are faded and not readable in my shop. It does appear to be a range of numbers and first one starts with a 2...maybe 25 or 26 or 28. John Hart did send me specs on his (270-324mfd) but not sure how similar our motors are. I've sent John specs on my motor.

If I can't make out numbers on capacitor, how can I determine correct size? I've had no luck trying to google a parts breakdown of motor.

I got the info from motor which is:
Table Saw model: 113.298720
Motor model: 62618
14amp
110VAC
.75HP

[John Hart]

Britt...I was able to find a forum with a three-year-old discussion about this motor (62618) but on a different saw. The specs that a guy got off his motor was:

Capacitor manufacturer..Mallory
216-259 Mfd, 110VAC
C10-109234B-170
235-7616K-05

And for whatever it's worth....I have an old Craftsman Radial Arm Saw that has the same symptom as your tablesaw. I switch it on....and it grrrrrrrrrrrrrrrrrrrrs up to speed. If I was stupid...I bet I could stop it with my fingers. :D It doesn't take much of a pinch to stop the blade when cutting thick pieces.

Maybe I'll try to replace the start cap on my RAS....just for fun :)

[Britt Lifsey]

Thanks John! What I'm making out as a 26x might be 216. Checked Grainger and they show 2 Dayton capacitors (same diameter different length). I'll measure mine this evening and hopefully one will match. I'll order order it and see what happens. Maybe it will ship as quick as yours did!

We're finishing up the finish on daughter's coffee table and want to start on a desk project for my son so I need to get past this soon :)

Thanks again to all for input!!!
PS - yeah, don't grab that RAS blade :)

[Steve Bigelow]

If you do discover that it is the bearings, you can easily revive these bearings if you have a vacuum chamber or access to one.

Pull the bearings and drop them in a beaker of 30wt oil, completely cover the bearings. Place them in the vacuum chamber and pull a vacuum on them for at least 4 hours. If you have a clear chamber, you will see bubbles coming out of the bearings.

Release the pressure and let them sit in the oil for another couple of hours. The oil will go back into the voids and re-impregnate the bearings. Good as new!

[Don Jarvie]

It may be time to invest in a new saw. Seems like you are doing quite a work and a more powerful saw may be nice.

You can start by saying, Honey, I'd be more efficient if I had a.....

[Britt Lifsey]

I ordered the start capacitor...if that doesn't work then maybe???

I would rather say "Honey, I saved LOTS of money fixing this table saw. I think I should spend the money I saved on a .........." :) :) :)

[Chip Lindley]

If the motor has been run excessively without oiling, the shaft ends will be discolored, burnt-looking or glazed over. Easy enough to discern. But, if the shaft ends are shiny and polished, I doubt you have bearing troubles.

IF the shafts are glazed, very fine crocus cloth can be used to polish them shiny again. Re-oil, and see how she runs!

[John Hart]

I ordered the start capacitor...if that doesn't work then maybe???

I would rather say "Honey, I saved LOTS of money fixing this table saw. I think I should spend the money I saved on a .........." :) :) :)


Well...just for fun...since you're waiting for your part. I think you can rule out mechanical problems. It spins freely by hand, and when you take it off the pulley, you have the same symptom. I would think of things that would cause low voltage.....Extension cords...dirty power switch...corroded ac plug...frayed wires...etc.

Keep in mind that shorted or open windings are very rare....but dirt is very common.

Spend the saved money on something you both want. I'm sure she wants power tools....so think along those lines!!:D

[Britt Lifsey]

Hmmm...might try bypassing the table saw switch this evening and plug directly into the wall outlet. I did check voltage at outlet and it was 120.x. No extension cords being used.

"Dirt" used to be very common in my little shop. The HF dust collector I bought last month is helping A LOT with that :)

You should've seen my wife's reaction the time I mentioned getting her a basketball goal for our anniversary.

[Britt Lifsey]

Just a final follow-up...a new start capacitor didn't help much, if any. After reading a post here where another member ordered a new motor from Grizzly through Amazon I checked their prices and found a 1HP replacement for $124 plus shipping. So, for a little under $150 I've got a nice new motor that starts up perfect. I almost went for a 1-1/2HP replacement but in end decided the old 1HP had cut anything I ever tried so why spend the extra $$$.

On my distant cousin, I heard he has some serious health issues and isn't able to do much so I didn't bother contacting him. He is type that would've overdone trying to be accommodating and I didn't want that.

I might try to use the old motor to build something like a disk sanding station or other project I've seen posted here...something not critical to working in the shop if motor decides to not start! NOW, if this 105 degree weather would cool off me and son could move on to his desk project :) :) :)

One final thanks to all that offered ideas. Beyond just the basics, I didn't really have tools, experience or time to do fool with this.

[John Hart]

Glad it's up and running Britt. With this current cold spell that we'll get over the next few days, it looks like your timing is perfect. Maybe you could put a fan blade on that old motor and cool down the shop!!:)