How do you adjust the belt tensioner on a 1990 gmc vandura?

To adjust the belt tensioner on a 1990 GMC Vandura, first, locate the tensioner pulley, which is typically accessible from the front of the engine. Use a wrench or breaker bar to rotate the tensioner counterclockwise, relieving tension on the belt. If the tensioner is adjustable, you may need to loosen a bolt or nut to set the desired tension before retightening it. Finally, ensure the belt is properly aligned and has the correct tension before starting the engine.