How do you adjust fan belt tension on a 1985 911 carrera?

To adjust the fan belt tension on a 1985 Porsche 911 Carrera, first, locate the tensioning bolt on the alternator. Loosen the bolt slightly, then adjust the alternator's position to achieve the desired tension on the fan belt; it should have about a half-inch of deflection when pressed down at the midpoint. Once the correct tension is achieved, retighten the tensioning bolt securely. Finally, check the belt for proper alignment and ensure there are no signs of wear or damage.