Troubleshooting Dayton TEFC 3HP single phase motor (industrial table saw)

Thread Starter

jherrick

Joined Jan 1, 2022
3
Happy New Year,
Good to find and join the forum.
I found some similar info but a few years old.
Equip: 1996 Dayton 3Z997A 12" Tilting Arbor Table saw
Motor: Dayton 6K145 (3HP, 3500RPM, capacitor start capacitor run, 230v single phase)

I'm hoping someone with more experience than I would offer some advice on two points.

Initial problem:
Saw stopped during long rip cut.
After clearing, motor would not restart (sounded like it was attempting to run similar to a failed start cap)
Saw was put aside for several years.
I recently got back into the shop (retired) and after using a smaller saw really missed the power and capacity of this one.
I pulled the cover off the motor expecting to see separate start and run caps. however I found there were two 455MFD 125vac cans (pics attached).
1. I'm guessing this is the start circuit with the two caps wired in series to accomplish twice the voltage and half the value. Hoping someone more knowledgeable can confirm.
I found one of the connections was evidently not crimped securely and was loose (shown in the pics). This is an easy fix.
2. This may be a secondary issue requiring another fix or the result of the initial problem.
The arbor/blade does not spin readly with power off. Not able to attach a video however it doesn't appear to be a bearing issue as 20211231_154436.jpgcap2.jpgcap1.jpg20211228_174841.jpgwhen I spin the motor at the fan there is some resistance until a certain point in the rotation and then it springs forward.
My question is, would this indicate an internal issue with the motor or more likely caused by a belt tensioning issue (The saw uses 3 drive belts)
Thanks for any help!
jherrick
 

Tonyr1084

Joined Sep 24, 2015
6,863
Can you spin the motor freely without the belts on? Sometimes belts that have been held in tension for a long period of time without changing position can sort of freeze that way. I'd fix the cap wiring and disconnect the belts and see what happens. Obviously you can't do any harm that way, so it's worth a try. And if it proves to be the solution then get new belts.

Also while the belts are off see if the blade can spin freely. That should have no issues at all. If it does then the bearings (or bushings) need attention. I just had a small shop vac disassembled yesterday on my workbench. The motor would spin freely, but when shutting down it would scream and holler as the bushing was somewhat worn. The back end had the bushing, the front end had bearings. Cleaned and lubricated (with automotive transmission fluid) the motor is running happily again. But given that the bushing is worn I suspect this fix won't last for long.
 

Thread Starter

jherrick

Joined Jan 1, 2022
3
Can you spin the motor freely without the belts on? Sometimes belts that have been held in tension for a long period of time without changing position can sort of freeze that way. I'd fix the cap wiring and disconnect the belts and see what happens. Obviously you can't do any harm that way, so it's worth a try. And if it proves to be the solution then get new belts.

Also while the belts are off see if the blade can spin freely. That should have no issues at all. If it does then the bearings (or bushings) need attention. I just had a small shop vac disassembled yesterday on my workbench. The motor would spin freely, but when shutting down it would scream and holler as the bushing was somewhat worn. The back end had the bushing, the front end had bearings. Cleaned and lubricated (with automotive transmission fluid) the motor is running happily again. But given that the bushing is worn I suspect this fix won't last for long.
Thanks guys for the responses,
Agreed and thanks for the advice. I'm hoping it is a belt memory issue. They are the originals, there are 3 of them and it has been sitting a long time. It also needs a thorough cleaning.
I have not removed the belts yet but I'm about to take the table off to make things easier. The motor bearings seem smooth when I turn it from the fan.
More work to do. Thanks again-JH
 

Thread Starter

jherrick

Joined Jan 1, 2022
3
Worked out well.
New connector on the cap and new belts.
The motor ran fine without the belts on (the old belts were a mess).
I cleaned everything and greased the gears while I have it apart.
Running the belts a bit and I'll re-tension before I put it back together.
Now to find a new rip fence and a riving knife that will fit.
 

MisterBill2

Joined Jan 23, 2018
11,579
A poor crimp connection is a failure waiting to happen. And while perfect crimps are rather good, there are so many ways to produce a less than good crimp. And of course a crimped connection is seldom able to be taken apart for service.
 
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