Sunday, December 18, 2011

How to Re-wire a Potted Motor, Part 8: Motor Housing Removal

Now that we’ve got the motor leads disconnected (as shown in Part 7), we need to remove the motor housing in order to access the motor.

To get to the motor housing, we first need to remove the handwheel. I would ordinarily also disassemble and remove the bobbin winding assembly, but because that is an operation in its own right, I will save that for another entry and leave it attached to the motor housing. (Leaving the bobbin winding assembly on is not “standard operating procedure” for me, but as long as we are careful, we should be fine.)

We start by loosening the set screw in the stop motion wheel:

Don’t take it out all the way, just loosen it to the point shown in the photo below. Leave it in place to reduce the chance of losing it (I often see these missing on Singers I acquire). We only need to loosen it enough to get the stop motion wheel off.

Unscrew the silver stop motion wheel. Unlike the photo, in reality you’d have to use your other hand to hold the handwheel steady, but my other hand is holding the camera. Remove it carefully, keeping at least four fingers on it at all times, so it doesn’t fall out and chip the enamel on the handwheel (been there, done that).

Next pull the washer out by pinching one of the protrusions between two fingernails. If you’re not careful with the washer it, too, can suddenly fall out and chip the handwheel's enamel.

Now grasp the handwheel firmly and pull towards you. If it doesn’t slide off easily, wiggle it north-south and east-west while pulling it towards you.

Even with old grease sticking it in place, it should eventually come off with just hand pressure. (If it does not, tell me in the comments and I’ll prepare another entry showing you what to do.)

Now we turn our attention to the handwheel, and a choice of how to proceed. My preference is to clean parts as they come off of the machine, so I can store them clean while I finish the job. I also don’t like to handle dirty parts and then work on electrical stuff. So before I go any further I’m going to give this handwheel, the fiber gear, and the handwheel housing a cursory cleaning. You can of course skip ahead, because we’re on the internet and I can’t see you. And if I can’t see you, I can’t nag you.

To clean the handwheel’s innards I use these two implements that I bought for a few bucks at an art supply store, I believe they’re used for sculpting clay. (You don't need to buy these, read on.)

The one on top has a flexible metal tip. The one on the bottom has a silicone tip, here’s a close-up:

I use the metal one on the metal parts and the top of the gear, scraping the grease off.

The silicone one I use to “squeegee” between the gear teeth.

Every morning when I get my coffee-to-go at the diner, the diner guy gives me a wad of napkins. He probably thinks I’m going to use them to wipe my mouth after drinking the coffee, and he’s wrong.

I could do a whole entry on how to clean a handwheel, and one day I will. But I have to finish this series first. In any case, I get the wheel looking like this:

You don’t have to get it that obsessively clean, but I’d at least get the bulk of the old, hardened grease off of the thing. If you don’t want to buy the tools I mentioned above, you can probably find something in your kitchen. I wouldn’t recommend toothpicks--you don’t want splinters in the gear teeth--but maybe some plastic utensils, or one of those little plastic swords they put in cocktails.

If you clean the black part, I’d advise not to use anything other than a wet Q-tip and a lot of elbow grease. The bobbin winder tire rides on the inside of the handwheel, and if there’s anything slippery on it, like the sewing machine oil some people use to clean their machines, the tire will slip and the oil will eventually rot the rubber.

Handwheel finished, now we turn to the housing. In this case it’s pretty filthy; this machine is from 1937 so the lint is probably historic.

I remove the lint and hair with a small bristle vacuum attachment.

Then I go at the inside with the metal clay tool and burn through some more diner napkins.

Afterwards I scrub the insides with Q-tips moistened with rubbing alcohol. (If you go this route, be careful not to spill any alcohol on the outside of the machine. Alcohol is fine on bare metal, but it will eat through, and ruin, the exterior finish.)

Now it looks a damn sight better than before:

More importantly, with all of the excess grease gone, now I can actually see the two mounting screws inside.

We need to remove those two screws. A Brownells bit #360-6 fits perfectly. These two screws are often in there REALLY tight, so I often stand up and lean my body weight into the screwdriver, really pressing it into the screw, and then begin loosening it. To do this I often have to hold the machine with my other hand, but again, my other hand is holding the camera.

Once the screws have been removed, here’s how we’re going to remove the housing. You know how in the movies, when somebody’s fake-driving and just wiggling the steering wheel back and forth? That’s the motion we need. Do this GENTLY, please, and use both hands. My left hand is on the camera, but should be where the red lines are in the photo below. Be careful NOT to grab the bobbin winder assembly.

The extremity of the tilting of the housing is exaggerated in these photos, just to give you the idea. Do this as gently as possible!

As you continue wiggling the housing back and forth like a steering wheel, pull it towards you. Eventually you’ll feel it loosen and you can slide it off of the shaft. Easy does it.

Now your motor’s off. Set it down and go pour yourself a cocktail (even though you might be out of swords).

Go on to Part 9: Removing the Grease Wicks


  1. Brilliant Rain. Do you ever use lacquer thinner or mineral spirits to get rid of grease? What kind of solvents, if any, would the fiber gear withstand? What's it made of, amphenol? A suggestion: one way to loosen over-tightened machine screws is to use an ordinary carpenter's brace. It gives you quite a bit of torque and a surprising amount of precision. Let me know if you'd like one--I never recall seeing any around NYC when I lived there. Looking forward for the next installment.

    -Anonymous Comment-Leaving Person

    1. By 'carpenter's brace' do you mean a brace and bit like my father the plumbing used 50 or 60 years ago when I was a kid? I have two Singer 201's and am unable to budge the motor housing screw. Soaked and resoaked in PB blaster and heated but still no success. Two others came off like butter! Thanks for your suggestions. Kath (Vintage Singers Yahoo Group)

  2. "Do you ever use lacquer thinner or mineral spirits to get rid of grease?"

    Because I work indoors, I avoid both of those substances as I can't tolerate the fumes. On any metal part I use rubbing alcohol to break up both old grease and old dried-up oil.

    "What kind of solvents, if any, would the fiber gear withstand? What's it made of, amphenol?"

    The fiber gear is made of a material called Textolite, which is a composite of fiber and an unspecified polymer/resin. I never use alcohol or any solvent on the fiber gears, as I don't understand the chemistry well enough to know how they will affect the material, and replacement are no longer being manufactured. I only clean them with water and a small amount of Simple Green. You can use a toothbrush and/or thick string to "floss" the teeth.

    Thanks for the offer of the carpenter's brace, but thus far I've never encountered a screw I couldn't loosen with the right bits, the right handle and leverage.

  3. Very nice post,Rain. I see that those wires are pretty bare, making me believe that my motor is in similar shape and that there is hope. I had better get busy practicing the underwriter knot. I wish I had better heat in my shop......I wonder if Steven will mind too much if I commandeer the dining room table?

  4. An wooden "orange stick"/cuticle pusher which is found with the manicure implements has a pointed end and a beveled end also works for cleaning the fiber gear, tho I would really like to find one of those silicone ones!! Thanks again Rain, you are a great teacher!
    Diana in CNY

  5. Next time I am definitely having the cocktail at the required stage!
    Great post, as always.

  6. Thank you for doing these tutorials. I've recently acquired a 1938 Singer 201 with no. 48 cabinet and I am following along to learn how to rewire this machine. Today, I'm trying to remove the handwheel, but after removing the silver stop motion wheel and washer, I'm having trouble removing the handwheel itself. I've turned the wheel several times to the right and left and have tugged at it, but it's only budged a little. Do you have any suggestions as to what I should do now?


  7. Sewingnoob, turning the wheel is not going to do anything. Try wiggling it north-south and east-west, as stated in the directions above, while pulling it towards you. Do it for a full two minutes and let me know how it turns out.

  8. Rain, after following your advice, I was finally able to remove the handwheel. It took a lot of effort because it was stuck on very tightly due to globs of old grease. I've cleaned out the worm with alcohol and scraped the grease off the handwheel, and now I ready for more! ;D


  9. I can not get the motor housing off the machine. I removed the 2 screws and most of the wax built up. No chemicals were used. Does it need to be spotless inside to remove the housing? Love your tutoral thanks so much for the pictures and easy language
    Judy in Ohio

  10. Dear Rain,
    I wrote earlier that I could not get the motor unit off the machine. I took a hair dryer to it and the unit came off

    Judy in Ohio

  11. Historic lint! Love the "shop talk"! This blog is the best.

    I've already followed your excellent instructions on removing/cleaning and replacing the bobbin case and hook assembly area on my newly acquired 201-2. Cleaned and oiled the whole "front end" of the machine, actually. I'm here re-reading (for the third time) this "how to re-wire" article, as I patiently wait for my Bushnell bits to arrive in the mail - not messing with the wrong bit when it comes to removing that worm! And I'm a lefty, so I need all the help I can get. I did remove the handwheel to see what I'm up against in that department and sure enough, the worm is sitting in a big blob of grease...surprise!

    Historic grease.

    Rain, I do hope you put an article up regarding the removal, cleaning, etc. of the bobbin winding assembly. I'm not touching mine till I have directions from the best of the best!

    What a great help you have been...Thank You!

  12. Rain, love your blog as do all the Vintage Singer addicts! So I am trying to remove the posted motor on a 15-91 and I'll be danged if either me or hubby can get those so and so screws to budge. They been oiled, PB blaster and heat but no luck. Any ideas for me Rain based pon your experience and what particular cocktail do you find calms the nerves lol. Thanks for all the time you put into your wonderful tutorials. Kath

    1. Hi Kath, the absolute most important thing is that you've got the correct-sized bit, in this case a Brownells 360-6. By driving this bit hard into the direction of the nose of the machine (I stand and put my full body weight into it), I've been able to remove even the most stubborn motor mounting screws. Whatever you do, don't use the wrong bit and strip those screws--major hassle!