How can I find the right size belt for my sewing machine?

These belts are sized by their circumference in millimetres, so an MB340 belt is 340mm around. The best way to find the right size is to check for a number printed on your old belt, or carefully measure the total length of the old belt if it's stretched or broken.

Is it difficult to fit a new motor belt myself?

Fitting a new belt is usually straightforward. You'll typically need to loosen the motor mounting screw to create slack, slip the old belt off and the new one on, then pull the motor back to tension the belt before tightening the screw again.

What are the signs that my current belt needs replacing?

Common signs of a worn belt include the handwheel feeling stiff or the machine running slow, noisy, or inconsistently. You might also see visible cracks, fraying, or shininess on the old rubber belt itself.

Machine V Belt | Serrated Motor Drive | MB Series 300-400 for Sergers

Name: Machine V Belt | Serrated Motor Drive | MB Series 300-400 for Sergers
Brand: Compel
SKU: VBEL-00003
Price: 6.95 USD
Availability: InStock
Rating: 4.7 (213 reviews)

Stock #:CMP-04580

SKU:VBEL-00003

Machine V Belt | Serrated Motor Drive | MB Series 300-400 for Sergers - Image 1

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Machine V Belt | Serrated Motor Drive | MB Series 300-400 for Sergers

$6.95

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Questions about this product

How can I find the right size belt for my sewing machine?: These belts are sized by their circumference in millimetres, so an MB340 belt is 340mm around. The best way to find the right size is to check for a number printed on your old belt, or carefully measure the total length of the old belt if it's stretched or broken.
Is it difficult to fit a new motor belt myself?: Fitting a new belt is usually straightforward. You'll typically need to loosen the motor mounting screw to create slack, slip the old belt off and the new one on, then pull the motor back to tension the belt before tightening the screw again.
What are the signs that my current belt needs replacing?: Common signs of a worn belt include the handwheel feeling stiff or the machine running slow, noisy, or inconsistently. You might also see visible cracks, fraying, or shininess on the old rubber belt itself.

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This is a replacement motor drive v belt for many home sewing machines, sergers, and overlockers. If your machine is slipping, running slow, or won't run, a worn-out belt is likely the reason. This v belt transfers power from the motor to the handwheel. It gets you sewing again. Features and Benefits - Serrated inner surface - The teeth on this v belt grip the motor pulley. This delivers consistent power without slipping for more even stitches. - Standardized MB series sizes - To find the right fit, check the number on your old belt. The number (e.g., MB340) tells you the belt's circumference in millimeters. - Flexible rubber compound - Resists cracking and stretching. This happens over time from heat and use. It makes it a good sewing machine replacement belt for modern or vintage machines. - Simple to install - You can often replace a serger motor belt by loosening the motor mounting screw. Then fit the new belt and retighten the motor to create proper tension. Applications - Replacing a broken or stretched belt on a home serger or overlock sewing machine. - A maintenance part to bring back power and speed to a machine that feels sluggish. - Refurbishing a vintage sewing machine that has its original, dried-out belt.

Material: Rubber. Application: Home Sewing Machine Motor Drive. Belt Type: V-Belt. Length: 300mm, 320mm, 340mm, 350mm, 360mm, 380mm, 400mm. Series: MB Series. Belt Length Options: 300mm, 320mm, 340mm, 350mm, 360mm, 380mm, 400mm. Material: Rubber. Operating Temperature Range: -20°C to 80°C. Abrasion Resistance: Good. Application: Motor Drive for Sewing Machines, Sergers, Overlocks. Belt Profile: Serrated. Flexibility: High. High-Concerned Chemical: None. Noise Level: Low. Product Type: Home Sewing Machine Motor Drive V Belt. Series: MB Series. Set Type: No. Tensile Strength: Approximately 100 N/mm². Wholesale Type: No. Q: How do I figure out which MB series belt size I need? A: The number corresponds to the belt's length in millimeters, so an MB340 is 340mm in circumference. The easiest way is to check the number printed on your old belt or look up the part in your sewing machine's manual.. Q: How do I figure out which MB series belt size I need? A: The number corresponds to the belt's length in millimeters, so an MB340 is 340mm in circumference. The easiest way is to check the number printed on your old belt or look up the part in your sewing machine's manual.. Q: How do I figure out which MB series belt size I need? A: The number corresponds to the belt's length in millimeters, so an MB340 is 340mm in circumference. The easiest way is to check the number printed on your old belt or look up the part in your sewing machine's manual.. Q: What are these belts made of, and will they stretch? A: They are made from a synthetic rubber that resists oil and heat from the motor. They are designed not to stretch, which ensures your machine runs at a consistent speed.. Q: What are these belts made of, and will they stretch? A: They are made from a synthetic rubber that resists oil and heat from the motor. They are designed not to stretch, which ensures your machine runs at a consistent speed.. Q: What are these belts made of, and will they stretch? A: They are made from a synthetic rubber that resists oil and heat from the motor. They are designed not to stretch, which ensures your machine runs at a consistent speed.. Q: Will this v belt fit my specific brand of serger? A: It should fit most home sewing machines, sergers, and overlocks that use an external motor with this type of belt. The key is to match the MB size, as that determines the length.. Q: Will this v belt fit my specific brand of serger? A: It should fit most home sewing machines, sergers, and overlocks that use an external motor with this type of belt. The key is to match the MB size, as that determines the length.. Q: Will this v belt fit my specific brand of serger? A: It should fit most home sewing machines, sergers, and overlocks that use an external motor with this type of belt. The key is to match the MB size, as that determines the length.. Q: Why does the belt have teeth on the inside? A: Those teeth, or cogs, allow the belt to flex around small motor pulleys without cracking or losing its grip. This results in smoother power transfer and a longer life for the belt itself.. Q: Why does the belt have teeth on the inside? A: Those teeth, or cogs, allow the belt to flex around small motor pulleys without cracking or losing its grip. This results in smoother power transfer and a longer life for the belt itself.. Q: Why does the belt have teeth on the inside? A: Those teeth, or cogs, allow the belt to flex around small motor pulleys without cracking or losing its grip. This results in smoother power transfer and a longer life for the belt itself.. Q: How often should I replace the motor belt on my sewing machine? A: There isn't a fixed schedule, but you should check it periodically for signs of wear like cracks, fraying, or a shiny, glazed surface. If the machine seems to be slipping or running slow, it's likely time for a replacement.. Q: How often should I replace the motor belt on my sewing machine? A: There isn't a fixed schedule, but you should check it periodically for signs of wear like cracks, fraying, or a shiny, glazed surface. If the machine seems to be slipping or running slow, it's likely time for a replacement.. Q: How often should I replace the motor belt on my sewing machine? A: There isn't a fixed schedule, but you should check it periodically for signs of wear like cracks, fraying, or a shiny, glazed surface. If the machine seems to be slipping or running slow, it's likely time for a replacement..

Machine V Belt | Serrated Motor Drive | MB Series 300-400 for Sergers

Questions about this product

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