TIL you can overtighten a serpentine belt tensioner pulley and wreck the bearing

I swapped my alternator on a 2005 Civic last weekend and cranked the tensioner bolt way past snug. 30 miles later the bearing seized and threw the belt off on the highway. Has anyone else cooked a cheap part by overdoing the tightness?

2 comments

2 Comments

avery_carr578h ago

Sucked to learn that lesson, @alice808, but at least now I treat tensioner bolts like they're made of glass and apologize to them first.

alice80810h ago

Oh man, that exact "way past snug" feeling got me too. I did the same thing on my 03 Corolla thinking more tightness meant more security, idk why I thought that. That bearing seized up so hard it actually melted a little plastic piece off the alternator housing. I mean, you just assume tighter is better for anything with a bolt, but cranking a tensioner like a lug nut is a guaranteed way to learn the hard way. Maybe it's just me but I still wince every time I see a belt tensioner now, like it's gonna come flying off any second.