Featherweight motor; Singer 221 motor

 This post is how I serviced a Featherweight motor.  I am not an expert.  This is the first time I have serviced this type of motor.  I offer, here, my experience in the hope that it will help.  I have the adjuster's manual for this machine but the photos are dreadful and dark.  

First thing: I got the  motor off the machine.  When I checked out this project last weekend I resisted.  Looking under the machine at the wiring deterred me.

That big white wire is the lamp wire.  It is encased in lead and the white stuff is oxidized lead flaking off and it flakes off everywhere.  I resisted following Rain's suggestion to remove the lamp wire and scrub all that stuff off.  I wish that I had just done it.  I am going to do that next.  YECH.

So anyway, I just did not want to delve into this motor work because of these wires.  But I had to.  So, here follows how I did it.  I did not start here, but as long as the photo is handy, I will explain that I loosened those two clamps freeing up the nasty lamp wire and the two motor leads. That allowed me some slack to work on removing the motor wires from the three pin terminal.  I left the little motor lead clamp in place right there.  I did remove it later but that is later.

To get the belt off of the pulley on the motor you have to loosen the screw that secures the motor to the machine.

See what I mean about all that nasty white stuff?

Once this screw is loosened, lift the motor up and get the belt off.  I took the screw all the way out to release the motor form the machine base.  I put that screw back into its home on the motor to keep it safe.
I then loosened the screw holding   Mr. Three Pin Terminal in place.

I gently pulled Mr. Three Pin Terminal away from the machine base to reveal the wires held in place with wire knobs.  The motor wires go to 2 and 3; color coded.  Lucky me.

The knurled knob for #3 loosened easily.  But number 2 needed persuading.  I do not recommend what I did, but it worked.  I ever so gently used my needle nose pliers to grasp the knob.  I tried at first with some cloth covering the knob for protection. Then I just went for it straight on .  It worked.  But I think it is a bad idea.  You could break those knobs.  Younger folk might have stronger fingers and not need the pliers.  Perhaps a piece of leather over the pliers would have worked as well.

Once both wires were free of  Mr. Three Pin Terminal  I fastened Mr. TPT back onto the machine.  This is when I loosened the clamps holding the nasty lamp wire and the motor wires.
I also, because I am somewhat anal, put some red tape on the #3 motor lead.  Hey, I need all the visual clues I can get.  This helped me stay organized.  I realize that the wire itself is red, but I wanted to be really really sure.  And I like marking wire with electrical tape.  It feeds my inner child.

Then I pulled the wires through the opening on the machine base and freed the motor.  I was very careful as I threaded the wires through that opening.  It is quite roomy, but I just wanted to be gentle to these 64 year old fixtures.

I then removed the brushes.  The brushes are worn down with the friction of rubbing on the commutator and they like to return home the way they were.  Otherwise the motor just has to wear them down anew.  So I marked how they came out with notes to myself on paper and taped the brush to the paper.

Here you can see the contour of the motor brush

And here you can see that I have a good half inch left on this brush.  Now I thought that I should replace these brushes as a matter of course. I had occasion to talk to Mr. Glenn Williams (http://pages.suddenlink.net/joyof301s/glenn.htm) and he advised that I leave the brushes.  He told me that of the 2800 221s that he has had pass through his hands, only three machines needed new brushes.

 I did scrub them with denatured alcohol, however.  Someone told me firing them with a blow torch works to clean them too.  I like the alcohol approach.

Next I removed the screws holding the motor housing in place

And then I shimmied the fiber insulation as far down the motor leads as I could toward the wire rings

I admit I did try to pry the motor housing apart at this point. When it  did not separate, I remembered reading about removing the pulley.  There is a set screw on the pulley  that needs loosening:

The pulley can then be removed and the housing gently pulled apart to reveal the armature and a very nifty underwriter's knot (circled)

I had to loosen that knot to gently remove the armature from the field coils.  I was VERY careful.  These motors are not cheap to replace.  They aren't making any more of them .

What a dirty armature it is.  I was very careful to secure the washers.  There is a fiber washer that belongs on the shaft near the commutator.

And two others, one a fiber washer, on the shaft at the other end of the armature. These came off when I pulled the armature.  I was lucky that I did not lose them.  Especially the fiber washer.  I have a feeling they might be hard to replace.

I cleaned the commutator with a pencil eraser and this nifty honing stick I bought from Ray White (http://www.whitesewingcenter.com/tools.php)

I love a clean armature!!!!

Once it was all cleaned I reversed the steps to put it back together.

This is a shot of the inside of the field coil.  I did clean this out gently being very careful not to disturb the soldered connections to the ends of the brush tubes

Then making sure that the fiber washer was in place I eased the armature back into the field coil.  I realize that the copper windings on this armature do not look clean.  I promise that they are.  I think that these windings, like the windings on the 201-2 motor , were varnished at the factory

 

Once the armature was back in place I gently tightened the underwriter's knot and eased the motor housing back into place. 

Then I replaced the screws.  I did have some trouble getting the screw near the underwriter's knot to slide in easily.  I had to adjust the wires some.  If I had tried to tighten the screw down on top of that wire I could have created one huge disaster.

 

Once the motor was securely reassembled, I replaced the pulley.  The pulley is held on with a set screw and the screw must sit in the flat on the shaft.  The flat is easily identified by the flat on the end of the shaft

 I replaced the brushes next being very careful to place them in the brush tubes (which I had cleaned out with a q-tip) exactly as I had taken them out.  It helped that I had taped them to a piece of paper.  I only had to pop them back in. ( I had already cleaned them with denatured alcohol)

Then I shimmied the insulation back up toward the motor and eased the wires back into the opening on the machine base.  I did fasten the motor to the machine base after I did this, just to hold things stable. 

I reattached the motor leads to Mr. TPT.  Then  I removed the wire clamp.  I tried to put the motor leads back in the clamp without removing it but it was too difficult.  There was a fiber "lining" that wrapped around the wires underneath the clamp. I really could not position it correctly without removing it and making some adjustments. 

Once I had the clamp back in place and secure, I then tightened the clamp holding the nasty lamp wire.  

It is not exactly as it was at the beginning, but it is good enough for an amateur.  I can make some adjustments and perhaps get the other "red" wire tucked up more neatly.  I have to remove the lamp to clean the lead casing so I bet that will get tighter once I have done that.