powermatic table saw troubles

[cellodoc]

[?][?] i have a powermatic 66 table saw.... it isn't working; when i push the green button, it just makes an angry humming noise, and the blade wiggles back and forth about a quarter inch... i then shut it down, or leaving it on causes a breaker trip. i found two grease points under the motor and generously lubed and spun the blade by hand to spread the grease and it worked for a day, but now the problem's back.... more lube yielded nothing...any thoughts??

thanks!! [^]


david turner

[Tom Slick]

sounds like the motor is burned out. the humming and wiggling is the classic symptom.

[cellodoc]

uggh.... what does that mean?? motor repair? new motor? just getting it out of the saw looks like a big job... any suggestions?

thanks!!

david turner

[Jim Boyd]

I would do a search on your saw with the words " starting capacitor" included before you tear it out of the cabinet.

[ironhat]

Most towns have an electric motor repair shop. Check the yellow pages and give the shop as much info from the ID plate as you can. They'll be able to tell you whether or not they will accept it. The motor removal will be a two man job - don't even think about doing it yourself. Ask the guy with the demolished back.
Later,
Chiz

[cgallery]

Take an air compressor and blast-out the inside of the motor. Get the air in through any vents you can find. I've had this problem occasionally and it often happens on units where sawdust has infiltrated the motor.

[Knottscott]

As previously suggested, it could be the starting cap, or it could also be that the centrigal switch is stuck closed. Check the cap first, it if it's not the cap, see if you can spray the back opening of the motor with WD40 and poke at the centrigal switch with a screw driver or some other probe...with the motor unplugged of course!

[cellodoc]

thanks, dustmight, but what is the centrigal switch?? i bought the saw at an auction some years ago, and have no owner's manual... i downloaded a current manual, but it doesn't even cover the grease points i have on my motor, so i don't have much faith in it... so what is this switch, and how do i find it??

thanks, david turner

[Wood_workur]

the centrigal switc is what turns off power to the starting capactior, which causes the motor to spin in the proper direction. If the saw starts after you turn it on and make the blade spin, then it is the starting capacitor. Seriously, if you decide to do that, be very very careful. Use a good sized piece of scrap wood.

[Tom Slick]

I forgot about single phase motors having starting caps [B)]. the local motor shop can check it out for you and get you a replacement capacitor if that's what is wrong. if the motor is burned out they'll probably tell you to it is cheaper to replace it, my local shop won't touch anything under about 10hp for that reason.

[monte]

And the blade wiggles back and forth about a quarter inch? You may want to check into the trunions, blade arbor, etc as well. Blade problems are not caused by a bad capacitor.

[JimD]

I agree with the post talking about dust in the motor. I would check out the switch and starting capactor first but if they are not the issue, then I would take the motor out and take it apart to clean it before heading to the motor shop - do this especially if you see no signs of overheating (i.e. if it isn't black anywhere). My old table saw had a 1hp induction motor (real 1 hp, weighs about 50 lbs) that would clog up every few years. I took it to the motor shop once and I think they were kind enough to just blow it out and give it back but I may have had to pay. After that, I just cleaned it out myself. You need to get the slots in the stator (the stationary part) empty of sawdust. When they got full, I could spin the blade for awhile to start the motor and then it wouldn't start regardless of what I did. If there are any slots on the rotor, I would clean those also. You need to be a little careful about what you use to clean them out. Air is fine but if you have to put something into the slot to push the dust out, use wood or something soft rather than metal. The stator is a bunch of thin punchings that are electrically insulated from each other. If you scratch through the insulation, you can cause the stator to overheat.

Jim

[sneezer17301]

please don't spray WD40, which is basically kerosene, into the starting switch area on a plugged-in electric motor. The air blast is the best idea I have read so far.There is probably dust on the start switch contacts. The wd40 will burn and also will short out the contacts on the starting switch until it dries. The centri-switch
cuts out the entire starting circuit when the motor reaches full rpm. the entire start circuit consists of a centri-switch a capacitor the starting winding and a starting switch. The direction the motor turns is determined by the direction the current is sent through the starting winding. most(American branded) motors can be reversed by merely switching the red and black wires. If everything is clean and shiny the culprit is probably the capacitor or a burnt start winding.

[cellodoc]

[|)]... thanks, folks for all the help... here's a credit to the wmh tool group people; i called powermatic tech support today and the guy there was pretty sure it's the start cap, and i called a local motor shop and he agreed...he told me how to pull the capacitors out, and i just did that and found the start cap is broken w/ liquid leaking out... I THINK THAT'S THE PROBLEM...[8)] my wife's taking the cap to the shop tomorrow, and hopefully he'll have a replacement or he'll order it... I hope this is the end of this problem... more later!!!!

david turner

[cellodoc]

update..... it was the start capacitor.... the motor shop guy had one in stock, i put it in, and the saw is back to its old self again!!! Take heart, troubled friends!! once in a while, even a big problem can have an easy answer!!