Replace bearings on a Sears 113 series/model electric motor???????

[Charles McKinley]

Hi all,

My motor finally gave up the ghost. Can someone point me to instructions on replacing the sleeve bearings on this 1 hp table saw motor? I believe it was made in the 80s.

Harbor freight wants more for a motor than I paid for the saw. I'm afraid the cost of a motor shop will be about the same.

Can the sleeve bearing be replaced with ones that don't need to be oiled? The saw gets loaned out on occasion. If not extension tubes will be added to make the caps easily accessible.

I haven't found a used motor either.

Thank you

[Jeff Erbele]

Hi all,

My motor finally gave up the ghost. Can someone point me to instructions on replacing the sleeve bearings on this 1 hp table saw motor? I believe it was made in the 80s.

Harbor freight wants more for a motor than I paid for the saw. I'm afraid the cost of a motor shop will be about the same.

Can the sleeve bearing be replaced with ones that don't need to be oiled? The saw gets loaned out on occasion. If not extension tubes will be added to make the caps easily accessible.

I haven't found a used motor either.

Thank you

I would try Sears first or their parts direct website for the bearing or a motor

I use to work in a motor rewind shop. How to replace them:
In the process, if you remove any wires, and they are not color coded or labeled; label them.
On a single phase, 110v that should not be a problem, but an ounce of prevention will prevent any problems
~
Remove the motor from the saw
Remove the pulley if it is a belt drive / drive coupler etc. as appropriate
If the motor is TEFC - Totally Enclosed Fan Cooled; remove the fan schrod and fan

Mark the end bells to ensure not mixing them up later and to aid in reassembly.
We always punched them with a center punch on the top of the motor:
2 marks for D.E. - Drive end
1 mark for O.D.E. - Opposite Drive End / Fan End if so equiped
That was for cast iron frame motors with bolts thru the end bells into the frame.
If you have a rolled steel frame (basically a tin-can) with thru bolts, it would be a good practice to index the end bells to the frame, meaning put some line-up marks across the split between the frame and end bells. It may help with re-assembly, eliminating rotating the end bells in attempt to get the thru-bolts into holes you can't see inside the motor.
You can use a permanent marker or scribe for that.

Remove the screws that hold the end bells to the frame.
~
Remove the end bells. This could be easy or difficult.
With sleeve bearings, if they are in good condition, it should be easy.
If they are worn badly or sized to the shaft, the task could be more difficult.
I would use a rubber-faced dead blow hammer and rap the end of the shaft. That will pop the back end bell off.
If you don't have a dead-blow, use a a 2-3 hammer or whatever you have with a hardwood block protecting the shaft so you don't mushroom the shaft end.

After you remove the ODE end bell from the shaft, you can repeat the proceed and rap that end of the shaft to pop the DE end bell out of the frame. ...or take the rotor out and use a block of wood thru the stator. A hammer handle works too.

Next remove the sleeve bearings from their seat. Depending on your skills and tool you have; this could be a task.
The fast easy way - set the end bells on 2 blocks or stand-off spaces and heat the bearing housing area with an ox-acetylene torch with a rose-bud tip or a larger welding tip. The end bells expand from the heat and the sleeves should fall out.

If you have O.A. torch and if you have aluminum end bells be care not to melt them. If you do, scrap the motor.
Aluminum will melt somewhere around 765 degrees F, depending on its composition.
You could use multiple ways to measure that, a 600, 650, or 700 degree welders temp stick, an infrared thermometer, or adjust your flame to a carbonizing flame, one with inadequate oxygen / excess acetylene / one that makes black smoke.
Smoke up the end bells with soot. The soot will burn off about 100 degrees lower than the melting point of the aluminun. That is your warning to stop heating the end bells.

If you don't have an ox-acetylene torch or access to one you could use a morgan-knocker / slide-hammer style puller with the right attachment. I don't know about MAPP gas, but a Propane torch likely will not produce enough heat fast enough.
They could be machined out on a lathe or vertical milling machine.
So far my guess is none of these are on your radar

If you have a die grinder or dremel, you can cut them out, just be careful not to damage the end bell. At least not in a major way.
You don't have to cut all of the sleeve bearing out. Either a slit or a groove, thinning the wall in one area or two opposite areas.

After you have them removed, clean up the housing and remove and burrs.

Installing the new sleeve bearings. They are held in place with a press fit.
Normally a hydraulic press or an arbor press is used.
You could heat the end bells with any torch or a bearing induction heater and maybe even with an electric frying pan, and simply drop the sleeve bearing in place.
Unless you have a bushing driver of the correct size pounding them in will not work. You will damage the new bearings.

After you have the new bearings installed, make sure the shaft journal is in good shape and re-assemble the motor in reverse sequence

RE: oil-less sleeve bearings? I don't think so, but it may be possible with modern day materials.

[HANK METZ]

..."Smoke up the end bells with soot. The soot will burn off about 100 degrees lower than the melting point of the aluminum. That is your warning to stop heating the end bells"...

That tip alone made reading this thread worthwhile, thanks Jeff.

[Lee Schierer]

Simply press out the old bearings and take them to your local bearing house along with the motor shaft. They can easily measure the O.D. of the bearings and the O.D. of the shaft and get you new sleeve bearings. Worst case they can sell you oversize ones and any machine shop with a lathe can turn them down to the needed diameter. You may also want some loctite bearing retaining compound to insure the bearings stay put. If you notice there are small plastic plugs on each end of the motor that you should pull at least once a year and put in a few drops of oil.

[Charles McKinley]

Thank you Gentleman,

The motor is no longer available through sears. Bearings might be still available.

Jeff thank you for the very detailed directions.

If I can't get them through sears I will take the parts and go to Erie Bearing in Meadeville.

Thanks again

[Jeff Erbele]

With sleeve bearings, usually the bearing journal is a nominal size, e.g. 5/8 .625; 3/4" .750"; etc. You can measure it with tape measure and be correct ...or a spring caliper and scale.

The sleeve bearing ID will be a few thousands .001" larger. The clearance depends on shaft size, speed, lubrication, radial load. etc. I can dust off my machinery's handbook if you need help.

Yes a bearing supply house should be able to help you. If not a machine shop can make the bearings for you. Likely the material is bronze. The problem is repair cost compared to a new motor or compared to a new or used saw.

When I worked in the machine and motor repair shop, every year the motor H.P. became progressively larger as to uneconomical to repair due to inexpensive foreign labor. Further motors were built as throw-a-ways. Cast iron frames were replaced with rolled steel, tin can motors. We never worked on fractional HP and single phase motors unless it was a specialty motor. It was uneconomical. Other wise we repaired 1 HP motors when I started; 20 years later 25 hp and even larger were questionable as to repair or replace.

[Jeff Erbele]

..."Smoke up the end bells with soot. The soot will burn off about 100 degrees lower than the melting point of the aluminum. That is your warning to stop heating the end bells"...

That tip alone made reading this thread worthwhile, thanks Jeff.

LOL Thanks Hank and you are welcome. I completed formal training as a welder, Ag mechanic and advanced machinist. I didn't have trouble getting a job and used all of my skills in industrial repair shops.

[Jeff Erbele]

Simply press out the old bearings.... .

It may not be as simple as that; usually the are pressed into a blind hole. The problem with small inexpensive motors is they are built inexpensively for quick assembly, with no regard to disassembly or repair.