# Serpentine belt tensioner



## danieljamieobrien.do (7 mo ago)

Hi I changed the serpentine belt was OK tryed to take tension off to adjust belt and now the bolt just turns? Any ideas why thanks


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## M_Bimmer (Dec 14, 2019)

Which way? (e.g. "one-direction" never loosens, or the "other-direction" never tighens?)...but both actually means stripped threads, by either cross-threading, or way-over tighening during the last install wrenching event.

If true, don't get too bummed.....depending on your skillset, this could be a cheap fix, or an expensive fix, but will still be a PITA...but more info is needed, model year, chassis code, and engine displacement..and we can go from there. 

Rule of thumb, always use a torque wrench when dealing with aluminum (not claiming your bolt is aluminum, although BMW does use aluminum bolts, but there is a high likelihood the material holding the bolt is aluminum)


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## danieljamieobrien.do (7 mo ago)

Thanks for reply its e53 3.0d 2003 its supposed to tighten anti clockwise the it can move same way to loosen tension but just turning now. The belt is tensioned now and runs fine but next time I need to remove or swap belt I will have an issue


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## M_Bimmer (Dec 14, 2019)

Out of curiosity, does the following look right for your '03 E53, N54? If so, which bolt stripped?










or if you have this configuration, which bolt?


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## danieljamieobrien.do (7 mo ago)

Neither its the single spring type with the 24mm nut in centre of pulley and that's what's started moving


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## M_Bimmer (Dec 14, 2019)

Sorry, I got the wrong engine...you have the diesel...but you answered the question....


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## danieljamieobrien.do (7 mo ago)

Hi I can just see the nut behind pulley if I can get a spanner on it I can tighten the front 24mm and job done


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## M_Bimmer (Dec 14, 2019)

Depending on verison, 1st image, item 3 requires the bolt, item 8, to be tighened within item 2.....where in the 2nd image 2, for item 2 requires the nut, item 3, to be tighened onto 4....


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## danieljamieobrien.do (7 mo ago)

Iv just tightened it up all good thanks mate👍🏾


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