In article <5ddcea74.0312011634.3a79f80e@posting.google.com >,
chip@chipanddebby.com (Chip Stein) wrote:

> It's a hydraulic tensioner. you can't overtighten them. first
> thing's first pop the belts off and isolate the noise. it may be an
> accessory. possible it's a tranny bearing but who knows. start with
> the basics.

It could be a vacuum hose...