Timing belt tensioners

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xavier
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Post Fri Apr 13, 2012 6:30 am

Can timing belt tensioners rattle?
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Brianmoooore
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Post Fri Apr 13, 2012 10:30 am

They contain ball or roller bearings, and these can rattle when they go dry and/or the cage breaks up.
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xavier
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Post Fri Apr 13, 2012 3:58 pm

Could this happen at just 1500rpm? Not above or below
kam-325i
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Post Fri Apr 13, 2012 4:37 pm

theorecticaly, yes, due to harmonics.....

you may also find it will rattle at 3000 and 4500rpm, but at a different pitch.

its the same effect as an unbalanced wheel wobbling at certain speeds.....

either way, change the tensioner.
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fixedwheelnut
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Post Fri Apr 13, 2012 6:14 pm

Belt tension can cause that rattle as well as belt rattles against the cover, especially when cold if it is too loose.

Check the water pump bearing as well while you are in the area.