Timing belt Optibelt 12 AT3 / 639 AP
- Brand
- OPTIBELT
- Category
- Power transmission
- Subcategory
- Timing belts
- Series
- Alpha Torque
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Tell us the quantity you need and request a quote by WhatsApp or email.
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Description
OPTIBELT 12 AT3 / 639 AP belongs to timing belt, part of our Power transmission range. Tell us how many you need by WhatsApp or email and we'll get back to you promptly with a quote for 12 AT3 / 639 AP and any equivalents.
When you need to replace a timing belt, start by matching the marking on the old belt to the new one. This Optibelt 12 AT3 / 639 AP belt is part of the Alpha Torque series and has an AT3 profile, a 639 mm length, and a 3 mm pitch. We carry it for maintenance, engineering, and purchasing teams across the US, Canada, Mexico, and South America.
To confirm this is the correct belt for your drive, read the back of the belt you are removing. The marking should show the profile and length that correspond to AT3 and 639 mm. If the old belt is worn or the marking is unreadable, measure the length and check the pulley grooves to confirm the profile. The 3 mm pitch is a key dimension that must match the pulleys.
Because timing belts are often replaced as part of scheduled maintenance, it is good practice to inspect the pulleys and tensioners at the same time. Look for worn teeth, cracks, or glazing on the belt, and check that the pulleys are clean and aligned. If you are replacing more than one belt on the same drive, order them together so the set is matched.
Send us the part number 12 AT3 / 639 AP by WhatsApp or email, and our team will confirm it for you. If you have the old belt in hand, include a photo of the back marking and the pulley area. We reply promptly and can help you verify the profile and length or suggest an equivalent if needed.
Dimensions
- Profile
- AT3
- Pitch
- 3mm
- Length
- 639mm
Frequently asked questions
- How do I confirm this belt matches the one I am replacing?
- Check the marking on the back of your old belt for the profile and length. This belt has an AT3 profile and a 639 mm length. You can also measure the length and compare it to the data. If you are unsure, send us the old part number or a photo.
- What does the 3 mm pitch mean for my drive?
- The pitch is the distance between the centers of two adjacent teeth. This belt has a 3 mm pitch, so it must be used with pulleys that have the same pitch. Using the wrong pitch can cause poor meshing and premature wear.
- What information should I send to request a quote?
- Send the part number 12 AT3 / 639 AP, the quantity you need, and any details about the drive or the old belt. If you have a photo of the back marking or the pulleys, that helps us confirm the correct part.