Need help with a 15-91
 

last week i bought a 15-91 from someone who didn't sew and had it only for the cabinet. i think it had been stored in the garage and it was filthy outside and under the base. the faceplate was so dirty the woman had told me it was bronze - but the bronze was an oily dirt that came off with cleaning. the handwheel wouldn't even turn without major effort, and then only barely moved. i couldn't resist the challenge, so i bought it anyway. the cabinet is in decent shape - a queen anne style that i will use even if the machine is beyond saving. hehe although i'm not ready to give up on it yet!

i've read all the how-tos on cleaning - enough that my head is spinning! cleaned & oiled under the faceplate, around the bobbin, under the main body, removed the handwheel and found that entire cavity packed with grease. it had hardened almost like candle wax, so i thought that was the problem and pried it all out. turned the metal pipe inside and the needle moved freely. i wiped out the area down to clean metal, added some lube to the gear below and on the handwheel, but was unable to get the gear below to move at all. i put the handwheel back on and the needle won't move again. i *think* i have the handwheel on correctly. i opened one grease pot (closest to the front) and the grease is still normal texture in it. i cleaned out what was easy to get to without removing the works inside and added a little more lubricant to it. i didn't do anything with the second grease pot. the handwheel still barely moves.

then i removed the screw on the front of the machine that appears to be at the end of the immovable gear. it is very wet with oil, but i couldn't see how to grab anything to try to force the gear to move from there.

any ideas? should i take off the motor and would that give me access to the back of that gear?

i'm new to the vintage machine bug, but have bought 3 machines in the past 3 weeks. i now have six: my grandma's 1917 66 Red eye treadle;
the 1961 Slant-o-matic Rocketeer 503a from an estate sale in 1989 that's my main machine;
my mother's Pfaff 360, also from around 1960, that is for my 26 yr old daughter;

the new ones:
another Rocketeer, identical to mine, for my 20 yr old daughter,
a 66 that was in a near-dead case, off of craigslist that was so bad i bought it more out of sympathy for the seller than anything. it's spruced up very nicely, however and now i'm loving it;
this 15-91 that is also cleaning up nicely, if i can just get the gears freely moving - at least i think that's the problem.

thanks for your help!

Hi [oregongirl],

First off, replace the set screw you removed from the gear. Taking it out and then trying to force the gear to move will only create a bigger problem.

A machine will "lock up" for one of three reasons. In no particular order,

1) Rust.

2) A "thread lock," in other words a small piece of thread has become wedged between two moving parts, jamming up the whole works.

3) The oil and grease used to lubricate the machine have gummed up over time into a sticky consistency.

In my opinion #3 is the most common. First rule out #1 and #2 by closely inspecting your machine, particularly the underside, with a flashlight.

If it's #3, the good news is it's easy to fix. With the last 15-91 I fixed that was frozen solid, I simply put the machine on its side so I could access the undercarriage. Then, using a Q-tip, I dabbed a few drops of rubbing alcohol on every part of the undercarriage where two pieces of metal touched one another. Rubbing alcohol penetrates into gummed-up oil and breaks it up, and best of all it evaporates completely, so it won't rust your machine.

After just a few minutes of letting the alcohol penetrate, I was able to rotate the handwheel slightly, but it was still hard. But this at least let me see where the *moving* parts of metal were on the undercarriage, and then I applied more rubbing alcohol at those points to break up the unseen gunk holding them together on the inside. Then, more turning of the handwheel to let the alcohol penetrate more.

Once all the gunk is gone and your machine turns over smoothly, you then want to oil all the moving parts down there.

Two tips if going this route: 1) Lay a towel down under the machine, and 2) be very cautious not to let the rubbing alcohol spill onto any painted part of your machine, or it will eat through the finish.

Vintage has given some excellent advice. Kerosene is a safer product to use than rubbing alcohol though. The kerosene won't harm the paint. I have a 15-91 that I cleaned up, it's a wonderful machine!

One way to tell if hardened oil is your problem is if you see a dark brown coating on parts that should be silver steel. If the previous owner used 3-in-one oil then the oil will harden and turn sticky. Only use sewing machine oil, it's made to evaporate, not stay there forever.

everything on the underside already moved freely, but after i read your answers i flipped it back over and sprayed with Blaster - i think Glenn had recommended it. the same thing happens - when i have the handwheel off i can manually turn the pipe that the handwheel sits on and everything moves freely. when i put the handwheel back on nothing moves.

with the handwheel off i can see the lower gear that the handwheel is supposed to turn. the one that is horizontal across the grease pots and that i think connects to the motor. that's the area that was solid with lubricant that had hardened like wax. actually the entire area behind the handwheel was packed with it.

can i safely spray that gear with the Blaster?

i don't think it's rusty and can't see anything like thread jamming it.

hmm, don't know if this is relevant or not, but all the oiling spots that have wicking in them seem dry. i've oiled directly on the moving parts but not through the wicking, so perhaps that's necessary in order for the oil to get through. i'll try that.

Do NOT oil the wicks in the grease tubes! Those are only meant for grease and if you oil them, that will send oil down into the motor which can and will kill it.

If your machine is turning over but locking up once the handwheel is in place, that either means your motor is locked up, or the handwheel needs to be cleaned along the part where it inserts into the machine. Common sense will take care of the latter problem, for the former problem look here:

http://vssmb.blogspot.com/2012/01/co...ted-motor.html

i didn't put any oil in the grease pots or other places where you put lubricant. there are some oil spots, like the presser bar, that have wicking in them. that's what i was referring to.

i've cleaned the tracks of the handwheel and put lubricant on it. with the handwheel off, that shaft turns fine and all the parts move until the handwheel is fully re-engaged. then nothing moves. so i'm guessing it's the motor. i haven't even plugged it in yet and was thinking to get everything working before i did that. plus there is a crack with a wire visible in the cord.

i've read through the Vintage Singer's blog - he's got an incredible amount of information! OH - i just connected the dots and realized that's you! you've got a great site - although it has sucked me in and i've spent hours over the past week reading your blogs. i was hoping for any answer other than that the motor needs to be re-wired. i don't know anything about electrical, although i saw your tutorial on the most basic electrical stuff you need to know. it's still a little intimidating to me.

thanks very much for the help. i don't want to give up on it! it's a pretty little machine and i've already gotten hooked on these things!

It's not necessarily that the motor needs to be re-wired, and in fact that's not what it sounds like at this point; if you're having a problem turning the machine over by hand, that indicates some type of physical obstruction and not an electrical problem. But you'll most likely need to open the motor up to find out what it is. The tutorial I've prepared on the blog should give you enough background to pull it off, and with any luck it will be something simple.

I have had better luck with rubbing alcohol than kerosene and that will damage decals, too - just about anything that will remove dried on oil will destroy decals - be careful.

that sounds encouraging - i can do that. i've gotta run to work but will try to disassemble when i get home.

i'm keeping everything away from the decals - they're too cute and in pretty good shape.

really appreciate all the advice! have a great day!