electrical spark

bullyboy56 · Post by **bullyboy56** » Fri Feb 03, 2012 12:40 am

motor hums w/ no movement.took off belt plugged only motor ,cord spark & smokes , dont know if i have to change the switch,or motor:

dusty · Post by **dusty** » Fri Feb 03, 2012 4:45 am

It sounds to me like you need a new cord and while you are doing that you might as well put on a new plug. This would be a good time to assess just how long the cord should be for use in your specific shop environment.

robinson46176 · Post by **robinson46176** » Fri Feb 03, 2012 9:34 am

dusty wrote:It sounds to me like you need a new cord and while you are doing that you might as well put on a new plug. This would be a good time to assess just how long the cord should be for use in your specific shop environment.

I put a new plug on my Mark VII this morning before breakfast. Some previous owner had cut the ground prong off of the one it had. I just changed the plug since the cord (possible original) was in very good shape. If I were replacing the cord I would use a 12/12.
12 feet, 12 gauge.

Just a personal choice. I often find the need for about a 3' + extension cord. I try to pick up the heavy air conditioner extension cords at yard sales usually for about .50 cents.

.

JPG · Post by **JPG** » Fri Feb 03, 2012 9:53 am

What is smoking, sparking? The cord? The motor? The switch?

If the cord is defective causing insufficient power to the motor it will hum and barely move.

If the motor is smoking, it may already be toast.

If the motor is sparking it may already be toast, but is itself the cause.

Motors without internal thermal cutoffs(SS motors) are quickly burned up if powered up and not turning. i.e. slow response turning off or repeated attempts will make them toast.

You may have a loose wire/terminal on the switch.

FWIW, cord replacement is a good idea and bigger wire(#12) is recommended.

dusty · Post by **dusty** » Fri Feb 03, 2012 2:48 pm

bullyboy56 wrote:motor hums w/ no movement.took off belt plugged only motor ,cord spark & smokes , dont know if i have to change the switch,or motor:

I think your question was answered in the original post.

JPG · Post by **JPG** » Fri Feb 03, 2012 3:04 pm

dusty wrote:I think your question was answered in the original post.

That original post raised more questions than it 'answered'. IMHO;)

English (even when 'properly' used) can be quite ambiguous.

timdgarry · Post by **timdgarry** » Fri Feb 03, 2012 4:48 pm

Where do you attache a ground wire to the Greenie on replacing the cord?

JPG · Post by **JPG** » Fri Feb 03, 2012 5:08 pm

timdgarry wrote:Where do you attache a ground wire to the Greenie on replacing the cord?

The frame of the motor.

A jumper from there to the headstock if you are worried about the switch, but the motor pan/mount screws will most likely take care of that(except when 'servicing').