Home SPO TVMaintenance & Repair Understanding Sewing Machine Belts

Understanding Sewing Machine Belts

by Sarah

Hey, Everyone! I’m Sarah at sewingpartsonline.com and today we’re going to talk about your sewing machine belt. They’re an important part of maintaining your machine. There are several different types of belts. There are V belts, lug belts, treadle belts, geared belts, round belts, and timing belts. In this video, we’re going to teach you the signs of a bad belt and how to find out which belt your machine uses. We’ll even show you how to install one. Let’s get started. 

First, how do you know if you need a new belt? If your belt is on the outside of your machine, you’ll see obvious signs of disintegration, cracks, or excessive slack to the belt. If your belt is on the inside of your machine, you’ll feel it struggle to sew or it will stop sewing altogether. These are signs you’ve likely got a bad belt. You may even hear a clicking sound from too much slack. If your feed dogs or hook are out of time, you need a new timing belt.

To find a replacement belt for your machine, go to our website, www.sewingpartsonline.com, and click on “machine parts”. Click on the make of your sewing machine. Use the search box to find the model number of your sewing machine. Simply click “belts” to find all the belts compatible with your machine. 

If that doesn’t work, we need to do some measuring. If your motor belt is on the outside of your machine, this is pretty simple.

If your machine’s motor is adjustable, loosen the motor screw and adjust the motor to the middle of the slot. Take a shoe string or twine and wrap it around the handwheel in the same spot that the belt would go.

Tie the shoestring tightly around the motor pulley exactly how your belt would go on your machine. Cut the shoe string or twine to remove it from your machine. Place it next to a ruler to measure the length. This measurement is the size of your belt. 

Do not take your original belt off your machine to measure it. The measurement will not be accurate.

If your belt is on the inside of your machine, you can do the exact same thing as long as you don’t have a geared belt. You cannot measure geared belts with the “shoe string” method.

You must first gain access to your motor. To access your motor, refer to your machine’s service manual. If you don’t have the service manual for your machine, visit us at www.sewingpartsonline.com/sewing-machine-manuals.aspx.

It’s usually just one or two screws that you need to remove to access the belt or belts. Not all machines have belts so you need to consult your service manual first. 

Now that you know the size of your belt, you need to determine which type of belt to buy. 

If you have a treadle machine, you’re in luck. All you need is one of our universal treadle belts. It will fit every treadle machine ever made.

Now, I like to break belts into two groups, geared belts and not-geared belts. That sounds silly, but if your machine uses a geared belt, you have to use the exact belt made for your specific model. A geared belt has ‘teeth’ that fit inside the groove of the motor pulley. There isn’t any wiggle room.

Let’s take a closer look at these belts to understand the differences.

A V belt is tapered on the inside like the letter “v”. We highly recommend these belts because they fit perfectly into the groove of your motor pulley and perform very well.

A lug belt is easily distinguished by its teeth. These teeth are tapered on the inside and act like the groves on your tires. If a V belt isn’t available for your machine, this is the next best choice. 

A lug belt is not the same as a geared belt. Do not use a lug belt in place of a geared belt.

A round belt, a.k.a. a stretch belt, is designed to stretch to fit measurements within a set range. For instance, this one replaces belts measuring 12” to 15”. You’ll notice that this belt is round like your finger. It doesn’t fit very well into the groove of your motor pulley. If neither a V belt nor a lug belt is available for your machine, you can use a round belt. However, it won’t perform as well. It’s really a “last resort” belt.  

Installing a V belt, round belt, or lug belt is easy. Simply loosen the motor screw and bring the motor as close to the handwheel as possible. The old belt should just slide off. Place the new belt around the motor and handwheel. Reset the motor to its original position and tighten the screw. Your belt should have between 1/4” and 1/2” of slack. 

Timing and geared belts are easier to remove but require much more precision when installing. If you install a geared belt incorrectly, you risk throwing your needle bar out of time. Raise your needle bar to its highest point and mark it with a sharpie. Then, mark the highest cog on your motor pulley. This way, if anything accidentally moves, you know how to line the needle bar and the motor pulley back up so the timing is synced. Remove the old belt and slide on the new belt. Replace any parts you had to remove to get to the belt per your service manual.

I hope this was helpful. To buy a new belt for your sewing machine, visit us online at www.sewingpartsonline.com. If you want to come hang out with our sewing community, visit us on Facebook at www.facebook.com/sewingpartsonline, Twitter @sewingparts, Pinterest, Instagram, Google Plus….we’re everywhere. Be sure to like this video, share this video, and subscribe for our next sewing video. 

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Pam Lagerquist August 12, 2019 - 8:06 pm

Hi I sent for 2 belts from you folks, the man I spoke with was very helpful and your company is efficient , helpful and customer service is excellent. Thank you.

Jhanna Knauf May 27, 2019 - 6:53 pm

Hi Sarah,

I have a mid 50’s Morse Zigzag machine. I replaced the belt when I got it, as it had a pretty cracked old belt, and since then, I have snapped two brand new belts. It will be sewing just fine, then get a high pitched sound but not sew and then the belt snaps. Could this be a too small of a belt? I am pretty handy with fixing and tinkering old machines, but I don’t have a manual for this one and can’t quite figure out why this would keep happening. Any suggestions would be wonderful! Thanks!


CustomerService May 30, 2019 - 3:49 pm

Hi Sarah!
We do not offer a manual for your machine; however, you may benefit from speaking with a technician. You can call us at 888-824-1192 and we can get you in touch with our technician.

Alyssa A Frazier October 29, 2018 - 6:32 pm

I have a Brother XR3774, everything looks to be internal and my manual only gives very basic maintenance. It sounds like the motor could be messed up, when I press the pedal it sounds like a clogged vacuum. The feeder is up, I unthreaded the machine, tried to move the handwheel a bit to help it along but the needle will not budge at all. It’s plugged in right and everything. I’m in the middle of sewing my daughter’s Christmas dress and now I can’t get it to work at all. I don’t want to try taking it apart without an idea of what’s wrong with it. Any ideas?? Please

CustomerService October 30, 2018 - 1:39 pm

If you could email us at info@sewingpartsonline.com, we might be able to be of further assistance. We look forward to hearing from you!

francis killilea June 11, 2018 - 6:16 pm

I have a sears kenmore sewing machine model 158.840. I put the belt on but it still will not move the needle ..the belt turns and it is tight anysuggestions

CustomerService June 15, 2018 - 10:15 am

Hello Francis. I would suggest trying to adjust your motor to make the belt loose. However, if your machine does not have an adjustment, then I would suggest trying a slightly longer belt. You can view the generic belts we carry below:


Beverly March 11, 2018 - 10:21 pm

Hi Sarah,
I have a Montgomery Wards sewing machine from around 1980.
Model UHT J1414
I have the manual but it doesn’t show how to replace the lug belt.
the handwheel doesn’t come off, and the body doesn’t open on that side,
so I can’t see how the belt can be removed–it’s not exposed.
Can you offer any info?

CustomerService April 26, 2018 - 9:08 am

The only options we see available is to call us at 888-824-1196 and ask to speak with our technician Dennis or take it to your local sewing machine repair place as Montgomery Wards machines are rare and getting even more so. Thanks

Robbins Scheirer January 27, 2018 - 12:59 pm

Sarah just received the belt for my Singer Merritt 2404 and it’s exactly the same as the belt I was replacing because of slipping when I was sewing. I installed the belt (thanks for the YouTube video) have adjusted it multiple times, but the motor is smoking. What now?

Sarah January 30, 2018 - 9:38 am

Oh no! Please give us a call and ask to speak with our technician Dennis. He will be able to help you – 888-824-1192

Pamela January 4, 2018 - 4:21 am

hi I have a Kenmore 120.491 Electric Rotary Sewing Machine, NOT SURE IF THIS NUMBER IS REFERRING TO THE TABLE. SERIAL # 220583, I think 1954 Do you parts for this machine and info on purchasing all accessories needed for sewing? ON THE FRONT OF THE MANUAL IT SAYS- (KENMORE ELECTRIC ROTARY SEWING MACHINE) MODEL IDENTIFICATION NUMBER 49, MODEL NUMBER 120.491, YEAR PRODUCED 1954

Sarah January 17, 2018 - 11:42 am

Hi, Pamela! I’m not finding that we are able to get any parts for that machine anymore. I apologize for any inconvenience.

Nik Saliu October 19, 2017 - 8:12 pm

I have a GK257B stretcher SEWING MACHINE IT USES LUG BELT for the motor-do you have that. Thank you

Sarah October 20, 2017 - 2:16 pm

Hi! I don’t have any information on that machine. Do you know the belt length?

Jane Massey October 13, 2017 - 2:55 pm

I need a timing belt for a Adler 153A

Sarah October 16, 2017 - 10:21 am

Hi! I have an Adler belt, but I’m not 100% certain it fits your machine. Please contact one of our knowledgeable customer service representatives at 888-824-1192. They can better help determine the proper belt for your machine. Thank you!

JOYCE J COLEMAN September 28, 2017 - 9:17 pm

Hi Sarah, I have an 1953 American Home Precision Sewing Machine that is inside the table. It is missing the belt and I dont know what type it takes. Is there anyway to determine what type of belt it needs? If so do you carry that particular type?

Sarah September 29, 2017 - 10:13 am

Hi! I bet that machine would work nicely with a new V Belt. We just need the measurements. Can you measure the length needed by following our video?

SHERRY DAVIS September 18, 2017 - 4:54 am

Dear Mrs l any,
I need sew machine belt for single sew machine belt.
Here is my address is
Sherry l. Davis
1425B.Madison. street.
Little rock ark,72204.
My phone number is 501 554. 6391.
How much will it cost with sew single belt.
Sincerely Sherry. L. Davis

Sarah September 18, 2017 - 12:08 pm

Hi, Sherry! Can you give us a call at 888-824-1192? We can help get you the right belt and enter your shipping information for you. Thank you!


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