And YMMV, but the first TB job (MY '85) I did there was beaucou sand in and around the pinch roller next to the crank (grit in bearing). It's not a critical item, but I replaced it. I think Porsche deleted it in later years. The point is although the tensioner has tight covers, the other accessories are exposed to any grit that is sucked up. Not to mention the larger crap that EW found which is everywhere.