Q: 2007 bmw 335i serpentine belt keeps breaking

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I have replaced the belt twice now, it keeps breaking apart. First time it passed through the crankshaft seal and into the timing chain. This time it looks like I got lucky and it didnt. I dont know why it keeps breaking.

My car has 130000 miles.
My car has a manual transmission.

Hi There, It sounds like you may have a tensioner pulley that may have a worn out bearing that may be putting additional stress on the belt as it turns. The other possibility may be that the tensioner pulley may be adjusted too tight. I would suggest having a professional from YourMechanic come to your location to diagnose and inspect your vehicle.

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