My guess is the motor has a bad capacitor or the windings in the motor are shorted. Did you happen to over heat the motor any time recently?

 

Is it tripping the breaker instantly or after a short period of time (and which one… house circuit breaker or the one on the saw)? That machine has a universal screamer motor (no capacitor btw) with a plastic housing. The brushes could be the culprit, which are easy to check, but usually won't cause the breaker to trip. If it's tripping instantly, then you have a short somewhere that needs to be tracked down. If it's tripping after a short period of time, I'd check for binding somewhere.

Unfortunately, if you did heat the machine up by pushing it too far, it is entirely possible that you have warped the plastic housing on the motor - which houses the rear bearing. If that is the case, you might as well toss the machine, as a replacement motor is more expensive than the saw itself. Here is an example of what a trashed rear bearing housing looks like on one of those motors:

Cheers,
Brad

 

Kelster58…all I've managed to date is check the bushings. They were full of sawdust, otherwise appeared
OK. Blew them clean with my compressor, as well as inside where they fit. Full of hope, I flipped the switch,
but same 'ol same 'ol! Haven't yet looked into the capacitor or windings. MrUnix…it's tripping the circuit
breaker immediately, before any attempt to run. I've plugged into another good circuit and that breaker
instantly blew, as well. Satisfied I haven't pushed the machine too far…the housing appears in good shape,
no evidence of burning, warping. No evidence of binding, with blade turning normal. I understand from what you say, I have no capacitor to check. Right? Very strange to me that all was working fine when I last used it 3 months ago. Has never before tripped the circuit breaker. As I said, it's tripping instantly, and I have NO idea where to check for a short. Thanks for your efforts to help…will be grateful for any additional help.

 

Any chance that the "bearing bushing" or "strain relief bushing" could be the culprit, causing instant
tripping of the circuit breaker?

 

Any chance that the "bearing bushing" or "strain relief bushing" could be the culprit, causing instant
tripping of the circuit breaker?

- Hugh37

Hugh37 has a good thought there. Can you disconnect the motor and just operate the switch. That should give you a clue about whether it's the motor or the conductor…...

 

Kelster58…I'll give that a try tomorrow…
thanks.

 

You could isolate the motor, but to do so, you will need to do it at the switch - you can't disconnect the wiring from the motor itself without opening it up:

To get to the switch, the plastic cover surrounding it needs to be removed (just 2 screws IIRC) - and then you can unplug the wires from the spade connectors

Also, the rear bearing is installed in either a metal or plastic 'cup' that then gets inserted into the motor housing. Unless it's really, really bad, you would not be able to determine it's condition from just looking at the motor housing externally. It doesn't take much distortion to allow the armature to come into contact with the windings. Just saying.

Cheers,
Brad

 

its pretty common for the rear shielded bearings on those motors to seize

its a pretty simple fix, but you do have to open the motor and need a set of bearing pullers; replacing with sealed bearings helps and should only cost you $6

 

i found this video set (there are three) to be very helpful

 

davezedlee…thanks. Warrants a try, I
believe. Question: would the saw blade
manually turn if the motor seized? For . For info of all, I bought this saw new in about 2010. I had not recalled, but found the original motor that had failed "some years. ago", reason unrecalled, but glad I had
kept it…for good parts? I'll tear into it
before removing the one in the saw.
Again, if the motor has seized, will the
arbor shaft/blade manually turn?
blade

 

CORRECTION! I bought this saw new in
about May, 2000.

 

the motor will turn, but you can see in my photos that the grease had turned to mud

the increased startup voltage required to get the motor moving is probably whats tripping your breaker, and could explain why it used to work before, but doesn't now…. things have solidified since the last time

when i opened my motor, there was sawdust everywhere, and even the power switch was encased in a block of compressed sawdust in a perfect molded shape of the switch's innards; MrUnix's photo shows how mine came (used from Craigslist)

$25 for the saw and a new bearing later, and everythings fine now

 

Thanks, davezedlee…good work & photos!
Mine doesn't have a fraction of that sawdust
buildup. Your problem was the rear bearing
& was a puller required! Any substitute tool?
Not a cheapskate, but if costly I may have
no future use for it. Are there loaners…and
where buy parts? online eBay, Amazon?

 

the rear bearing fits inside a plastic "cup" that then presses into the frame of the motor… if you're lucky, that cup hasn't melted at all

you WILL need some sort of bearing puller… the two arms on mine were actually too thick to fit in the small space between the bearing and commutator, so i had to improvise using the two "L" brackets in the photo

luckily i had this puller from when i replaced the bearings in a Craftsman router about five years ago; it was only $15 or so, and because i had it and had replaced bearings before, i knew i could figure out the saw… so, highly recommended

a 6200-2RS (10×30x9mm) bearing is a pretty common size; i didn't replace the front bearing, mostly because i couldn't figure out how to get at it

but the saw works fine

 

davezedlee…many thanks. I plan to purchase a bearing puller today and attempt the job. Anxious to see
inside the motor casing…expect to find the bearings are bad, then on with ordering replacements.

 

Bad luck today…shopped hard at Harbor Freight for a bearing puller that would do the job. The only one
available instore that looked like it would work was a set of three. I tried the puller on my original saw
motor (mentioned in an earlier post) and found it too bulky and no way could be made to work. Now, I'm
waiting on a friend, who thinks one of his may work. In the meantime I'm trying to remove the motor
currently in my saw…a nightmare, I'm finding. Surely not going about it the proper (simple?) way. Anyone
able to suggest a video? Or clear instructions? For info, I was able to see the problem with the original motor,
that prompted me to purchase the replacement years ago. The "gear end" of the armature assembly that fits
into the bracket was damaged, like the "gear" had stripped. To repeat, if anyone can help with a video or clear
instructions as to the proper way to remove my motor, I'd be most grateful! Thanks…

 

Four screws and it pops off IIRC.

Cheers,
Brad

 

Thanks, Brad! I was wanting to remove the motor intact with the bracket…many more than 4 screws! Anyhow,
with screws, nuts and bolts coming out my "yingyang" I have accessed the motor. Everything appears in
exceptional condition…very little sawdust, the bearings appear good, no wobble, move freely, etc., no
evidence of burning. QUESTION: with the saw blade back on and tightened, just how freely should it
manually turn? Mine will turned easily, but will not continue to spin…probably should not, right? With
everything looking so good, I tend to believe there's a short outside the motor, to cause the circuit breaker
to trip INSTANTLY. But with the cord in excellent shape and new on/off switch and overload switch, I'm
more baffled than ever. As I earlier mentioned, I plugged into other separate breaker outlets and the same instant tripping happens. With the armature assembly looking "like new", what's the likelihood the problem
lies there? Say, no chance, please! Your thoughts, again, if you will, in view of what I've described. Thanks!

happens.

 

Pop the switch out and open it up… see if the "rocker" level inside has burned out contacts, or if a sawdust pack is shorting out

 

Pop the switch out and open it up… see if the "rocker" level inside has burned out contacts, or if a sawdust pack is shorting out
- davezedlee

Stated in the original post that the switch has been replaced.. so that rules it out.

I'd grab an ohm meter and start tracing wires to determine where the short is. Unplug the switch and check the power cord, switch and wiring to the motor. It could be a crimped wire somewhere, but you have to narrow down where to look first.

Cheers,
Brad

 

Good suggestion, Brad. I'll put the ohmmeter to work. It was suggested that while I have
the motor out, I bypass the switches and go directly with the cord to the
motor wiring…just a quick touch to see if the breaker instantly trips…with
extreme caution, obviously. If that is recommended I NOT attempt, I might
call about the cost of having the armature assembly tested. Thoughts??

 

Good suggestion, Brad. I ll put the ohmmeter to work. It was suggested that while I have
the motor out, I bypass the switches and go directly with the cord to the
motor wiring…just a quick touch to see if the breaker instantly trips…with
extreme caution, obviously. If that is recommended I NOT attempt, I might
call about the cost of having the armature assembly tested. Thoughts??
- Hugh37

Ohm it out first, including the switch to verify it's working correctly. I wouldn't throw too much money at it (ie: taking it to a shop) since you can find those saws quite often on CL for about $50 or less. Troubleshoot it as much as possible before doing anything more drastic.

The one I had toasted the rear bearing housing (those are the pictures of mine I posted), so I just kept it around to use as a router table - I had made a custom extension for it and it worked great for that purpose, and I had two other saws, so it wasn't all that big of a loss. Then one day I ran across a CL ad for an almost identical saw for free ("Curb Alert" type ad). The guy had ran into it with his car - the plastic cabinet was broken and the stand was all twisted up. I didn't think it would still be there when I went, but sure enough - it was sitting there on the side of the road. So I got lucky

Cheers,
Brad

 

For info of All…I dismanteled my table saw motor, found little sawdust anywhere in it, removed the brushes
and found them to look good and clean, the forward and rear bearings appeared clean and intact, spun freely
and had no wobble, and all else was reasonably clean with no evidence of cracks or breaks. After reassembling
the motor and prior to reinstalling it, an "experienced" close friend suggested I wire the motor direct, bypassing
the on/off switch and the overload switch. I did so, tying the white wires together, but leaving the black wires
apart, until I plugged the cord into the outlet, then momentarily touching the black wires together. Result…
the motor instantly started running with no tripped breaker. So, I put everything back together and wired both
switches back in place. All done, I plugged into the outlet & to my dismay (to put it mildly) the breaker instantly
tripped. Next, I bypassed the overload switch by tying both wires together, plugged in…the SAME. To me it
suggests a bad on/off switch. How could it be…it's brand new just like the original? How can it be bad when
my multitester indicates it to be good? With the switch OFF, the ohms test shows it to be closed…with the
switch ON, the ohms reading was all 0000's, showing continuity or open. Help, again, please…where are my
diagnostics " full of holes"????

 

Sounds like you have the switch wired wrong… verify you are actually switching the line to motor leads and not actually just shorting the two when flipping the switch. This isn't the best picture, but the only one I have of the wiring to the switch:

Cheers,
Brad

 

REGRETS I've taken so long getting back…too many other things demanding my time right now. Brad, you
hit on it…I had miswired the switch. Can't believe it happened, since I took photos after removing the switch
cover. Today, after a heat/air serviceman (friend) informed me I'm needing a new heat/air system at a cost
of over $7,000, I asked him to take a look at my saw. Rather quickly he observed that I had wired the switch
wrong, causing it to short and trip the circuit breaker (CB). He wired it correctly and NOW no more CB
tripping, just a table saw running like new. Can't thank all of you enough who offerred help. You were
awesome and I thank you.