Take a look at this diag.
Put a good size socket or a breaker on the bolt of pulley/tensioner #3 (in pic). I think it is 14mm. You're going to want to have the wrench handle like it is in the pic; in the 2 o'clock position. Turn clockwise, but you're not actually tightening the nut as much as releasing the tension on the arm as you force it down. You'll see whay I'm talking about when you get in there.
Put a good size socket or a breaker on the bolt of pulley/tensioner #3 (in pic). I think it is 14mm. You're going to want to have the wrench handle like it is in the pic; in the 2 o'clock position. Turn clockwise, but you're not actually tightening the nut as much as releasing the tension on the arm as you force it down. You'll see whay I'm talking about when you get in there.
