Schedule a Meeting · Talk to a real woodworker: +1 937-890-5197 · 8:00AM – 4:30PM ET

GE 1 1/8 motor hums, pops fuse.

kurtzz3

Again, this is with a GE 1 1/8 motor in a Mark V made in July, 1981.

This happened right in the middle of a project. Without making any adjustments, I went to turn on the switch. The motor hummed for about 1 to 2 seconds when turned on then the fuse on power strip pops. The shaft never turns on its own.

I disassembled the head stock and removed the motor completely.

Since new capacitors are only about $7, I went ahead and replaced it. Still no go.

The motor turns by hand freely, with no binding or scraping sounds. The bearings feel fine and the pulley shivs do not contact the motor housing. I can hear the motor TRY and turn, but nothing.

I don't see any external relays and such. Are they internal to the motor?

What should be my next course of action. Thanks, all!

billmayo

I have had to replace the motor (internal & external) wiring on every GE 1 1/8 HP motor (dozens) that I disassemblied. The insulation breaks down and can short internally. Yes there are start winding points that you can clean while you have the motor disassembled. You should replace the bearings at this time too. I recommend sealed bearings for these motors.

kurtzz3

Are the problems you've encountered something easily repaired by an owner (I am reasonably mechanically inclined)? and the parts easily obtained?

I see a service on Ebay that will rebuild a motor for about $70 not including shipping both ways. I'm more concerned with the time that will take. I'd like to get up and running again as soon as possible, which is why I'd rather do it myself.

JPG

Problem cause : "power strip".

Problem detail : The power strip introduces considerable additional resistance to the power source. The motor draws an exceptionally large current when starting. The power strip and it's power cord are not capable of allowing startup current to reach the motor and it becomes slow to start. The circuit breaker on the power strip is grossly under sized to pass the startup current.

Problem made worse : The motor becomes starved for voltage and the startup surge time is greatly extended. This creates heat in the windings and the insulation may break down.

If all this happened you have a counter weight(aka boat anchor).

If the insulation has not broken down, it may still work if given adequate power supply as it attempts to start. No added power strip or extension cords. Minimum of #14 power cord of no more than a few feet long.

A second likely cause : The internal start switch is not closing when stopped. That prevents the start winding from becoming energized.

dusty

kurtzz3 wroteAgain, this is with a GE 1 1/8 motor in a Mark V made in July, 1981.

This happened right in the middle of a project. Without making any adjustments, I went to turn on the switch. The motor hummed for about 1 to 2 seconds when turned on then the fuse on power strip pops. The shaft never turns on its own.

I disassembled the head stock and removed the motor completely.

Since new capacitors are only about $7, I went ahead and replaced it. Still no go.

The motor turns by hand freely, with no binding or scraping sounds. The bearings feel fine and the pulley shivs do not contact the motor housing. I can hear the motor TRY and turn, but nothing.

I don't see any external relays and such. Are they internal to the motor?

What should be my next course of action. Thanks, all!

Open the motor for a thorough visual inspection.

kurtzz3

The power strip is not one of those little plastic household variety. This is a large capacity power strip designed for use around large power tools.

Are there any things to be aware of when removing the end plates for this motor? Springs that will shoot off into space, etc?

JPG

Ok so it is 'beefy'! If it has 'worked' in the past, go back to it after getting this running.

No there are no booby traps inside, but care needs to be taken so as to not add new damage. Before taking it apart, score the end cap and outer shell so it can be reassembled the same as before.(makes getting the tie screws back in easier).

Now once inside, check the switch contacts. Most likely they are failing to 'make'.

Give it the 'smell' test to detect possible burned windings.

I be curious what the beefy strip has for a power cord.

dusty

JPG wroteOk so it is 'beefy'! If it has 'worked' in the past, go back to it after getting this running.

No there are no booby traps inside, but care needs to be taken so as to not add new damage. Before taking it apart, score the end cap and outer shell so it can be reassembled the same as before.(makes getting the tie screws back in easier).

Now once inside, check the switch contacts. Most likely they are failing to 'make'.

Give it the 'smell' test to detect possible burned windings.

I be curious what the beefy strip has for a power cord.

Most probably a beefy cord and plug.

kurtzz3

I'm having a difficult time uploading a photo, so I'll add a link to the Home Depot equivalent.

http://www.homedepot.com/p/Belkin-10-Outlet-Surge-Protector-F9D1001-15-DP/100663223

JPG

A 15 foot power cord that is likely #14 or #16.

I would not use it for the SS.

Time to look at the start switch.

jsburger

kurtzz3 wroteI'm having a difficult time uploading a photo, so I'll add a link to the Home Depot equivalent.

http://www.homedepot.com/p/Belkin-10-Outlet-Surge-Protector-F9D1001-15-DP/100663223

It is only 15 Amp. Those surge protector strips are not designed to run motors. That is a bit lite for the SS. You need 20 Amp. As a surge protector it is probably fast acting so will trip immediately on an over current/voltage condition that the SS will provide. Ditch the power strip and try plugged into an outlet directly.

skou

"Product Weight (oz.) 4.04 oz"

Copied from the Home D link above.

I REALLY hope that weight is WRONG!

Thing only weighs 1/4 pound?

Sorry, there is NOTHING heavy duty, if

that is correct.

My cheap (I plug wall warts into it) power

strip weighs more than a pound, maybe 2.

And, it has a plastic case.

steve

kurtzz3

The coils are nice and shiny without any burns and there is no burnt resin smell (I'm familiar with that odor).

I've shopvac'd out lots of sawdust.

However, there is one thing that confuses me. It has to do with the "start switch" which I guess is controlled by a centrifugal mechanism. If I understand correctly, in the normal off (spring relaxed) state, this switch should be closed. I am seeing this switch open.

There are two white pads that run along the outer surface of a black wheel that is controlled by the centrifuge. The white pads control the position of the switch contacts. This wheel can move outward or inward along the shaft of the armature.

When running, is this wheel pulled inward toward the coils, or pushed outward?

It looks to me like the wheel pulls inward, but that would close the contacts when the motor is turning.

If the wheel is pushed outward, then that would mean two of the contacts on the switch are bent far out of place.

JPG

If it stopped 'starting' suddenly, I doubt bent contact arms are the cause.

As for what direction, a close look should reveal that.

A pix would help.

kurtzz3

I got the motor running! My confusion was that I thought the contacts that are made and broken when the motor turns were the parts I have labeled "A" in the picture.

I didn't realize that the contacts were actually hidden underneath the little rubber boot marked "B".

Anyway, I think the real culprit was a build up of grime on the armature shaft that was preventing the black plate that "A" rides against to smoothly move back and forth.

I cleaned that all up and replaced the wires that had aged and cracked insulation. You can see them also in the picture. I also made sure everything else was dust free and lubed.

Motor purrs like its new and no more popped fuses. I suspect it will need new bearings in awhile so I will have to shop around for a bearing puller.

Thanks all for the help!

JPG

WHEW!

All's well that ends well!!!

silenthope

billmayo wroteI have had to replace the motor (internal & external) wiring on every GE 1 1/8 HP motor (dozens) that I disassemblied. The insulation breaks down and can short internally. Yes there are start winding points that you can clean while you have the motor disassembled. You should replace the bearings at this time too. I recommend sealed bearings for these motors.

Bill, do you have any advice or instructions for replacing these wires? I've got a 1 1/8 HP motor with the same wiring issue, wires have deteriorated and need replacing. I'm assuming they are bad all the way to where they connect on the coil.

billmayo

silenthope wrote
billmayo wroteI have had to replace the motor (internal & external) wiring on every GE 1 1/8 HP motor (dozens) that I disassemblied. The insulation breaks down and can short internally. Yes there are start winding points that you can clean while you have the motor disassembled. You should replace the bearings at this time too. I recommend sealed bearings for these motors.
Bill, do you have any advice or instructions for replacing these wires? I've got a 1 1/8 HP motor with the same wiring issue, wires have deteriorated and need replacing. I'm assuming they are bad all the way to where they connect on the coil.

Yes, I leave about 1" of wire from the winding connections. I solder new wires to the 1" long wires. I use shirk wrap tubing over this soldered connection. Do not use electrical tape, liquid tape is OK. I believe the wires to the capacitor and start switch might be OK but should be checked by twisting on the wire insulation. You do not need to cut any of the coil wrappings or remove the coverings that connect the wires into the winding wires.

br549

The topic of this thread matches my situation almost exactly, so rather than start a new thread, decided to just ask my questions here.

I took my 1980's vintage motor apart to blow out accumulated saw dust and now it won't start. I removed the floating sheave as well, which I normally don't do, to give it a thorough cleaning from both ends. As it came apart, the armature started slipping out before I was ready, and I wonder if that has done some damage to the centrifugal switch.

In the off or stopped position, the contacts are closed, but not tightly. A piece of regular 20 lb. bond paper slides easily between the contacts. Should I just bend the arms for a tighter contact? The black plastic spring loaded mechanism of the switch slides freely and smoothly.

When I try to start, the shaft tries to move slightly and then returns to it's original position. I do not leave switch on long enough for it to pop a breaker. Tried running motor with it removed from the SS and same results. Spade lugs on switch were a little loose so I center-punched the rivets that hold on the lugs for tighter connection.

kurtzz3

You might try using an ohm meter to check continuity across the contacts. I took some 800 grit paper and burnished the contacts very lightly.

Another thing I did that may have been a contributing factor to my final success was the pulley on the other end of the armature. I notice while reassembling that it seemed to bind slightly on the armature shaft.

I knocked out the key and cleaned and scraped any build up of saw dust so that the pulley shims rode up and own the armature shaft without ANY binding at all.

My theory is that if that pulley binds at startup, then the belt will catch and motor doesn't get a chance to come up to speed. This causes a condition known as "back EMF" which would pop my fuse.