Thread: Replacement table saw motor

Originally Posted by Sadorus7

I have a craftsman table saw model 315.228490. The motor is running slow and I believe I need to replace it. The part is no longer available though (980962-00). Any suggestions on a substitute that will fit?

I doubt many people will know what motor is involved based on the model number of the saw,

For the saw to work properly you will have to match the RPM & HP (this should be on the motor name plate)

Unless you are handy at metal work you will also have to match the frame size/geometry and arbor size you will have to pull the motor out and measure these up.

Originally Posted by Sadorus7

I have a craftsman table saw model 315.228490. The motor is running slow and I believe I need to replace it. The part is no longer available though (980962-00). Any suggestions on a substitute that will fit?

Check first that the belt is not loose or worn. This will give the impression of slowed speed. If so, replace it.

Regards from Perth

Derek

Instead of buying a new motor just have it repaired that way you have no issues with different mounts etc
It will most likely be cheaper

Thanks for reply! What type of store should I look for to make a repair on the motor?

any motor repairing workshop will be able to do this for you.

for example:
emotors.co.nz

there should be a capacitor to run with the table saw, not only the saw motor you need to replace.

if you tell them what motor is for, they will be able to replace it with a similar motor

I had to replace my saw motor recently. you will need to watchout for the space within the table saw.

Its possibly a faulty run capacitor, as an alternative to the other suggestions. A motor repairer/rewinders will diagnose it for you. But it might be worthwhile replacing the motor. The plate on the existing motor should give a frame size. Those contractor saws only run a 1.5hp motor, which is usually an 80 frame size. If you are prepared to modify the motor mount, going up a frame size to a 90 would enable a 2 or 3 hp motor. Cost difference is minimal.

Ok, thanks. Will most motors using the 80 frame size mount directly with no modifications?

Size 80 is an IEC frame size. Since you're in the US, you most likely have a NEMA size motor, probably 56. Google for "NEMA Frame Size Chart" and match up your motor dimensions to be sure.

HOWEVER, that saw almost certainly uses an Open Frame motor. If the saw has been used much at all the motor will be packed full of sawdust. The sawdust can interfere with the centrifugal switch and prevent it from opening. That leaves the start capacitor connected and the motor won't come up to speed, even with no load.

Compressed air through the vents may be enough to clean it, but if not, you might have to open the motor and give it a thorough cleaning. A motor shop can do that for you at a price if you're uncomfortable with opening the motor. Google shows three motor repair shops in Columbus and a few more in the surrounding suburbs.

If your "runs slow" symptom is only under load and the speed is fine at no load then you have a different problem. As suggested above, check belt tension first.

One other thing, if your motor shaft has a flat instead of a spline you could have a loose set screw on the pulley.

Thanks so much!