You have no "adjuster bolt". You have a serpentine drive belt and it's tension is maintained by an automatic belt tensioner. It is a pulley mounted on a housing containing a "clock spring" that keeps the belt under a pre-set tension and compensates for belt-wear. It is released by a special belt tool or a flex-drive handle. Mark---Raleigh, NC
A chain adjuster is a device to adjust the chain tension on a motorcycle.
it is self adjusting .
Release - The Tension - was created in 1980.
Release Some Tension was created in 1997.
The tensioner is automatic, if it fails to tension the belt enough a new tensioner and belt should be fitted, beware it in not an easy job. Dave.
Check the alignment of the pulleys and make sure the belt is at the right tension. One end has an adjuster on it.
place appropriate size wrench (probably 15mm) on the bolt through the middle of the tensioner pulley and put clockwise tension on it, this will ease the tension on the belt enough to remove it.
IT is only about 3 bolts release tension losen bolts unplug wire follow step in reverse install new one (disconnect battery first
Drive the vehicle up on a ramp and look up from undeneath the car. There is a tension adjuster to the belt there. Loosen and remove old belt, replace and readjust for tension.
The tension pully is at the top of the front of the motor. (LEFT SIDE SINCE ITS TURNED.) You need a 1/2" breaker bar to get i believe. (I haven't done that in a while) The alternator is easy, there is a large screw in the back and a couple of wires to fight. If you get book from an Auto Store on the Achieva, it will show you. I have a Hanes book i believe. if you can understand the book, it will take you a 1/2 hr.
To change the alternator belt an a 1985 Chevy Celebrity: 1. Loosen the adjuster bolt and the mounting bolt. 2. Move the alternator to release the belt tension and remove the belt. Reverse to reinstall a new belt.
I believe you have to loosen two nuts and use a metal bar to set a proper tension.