How do you replace the alternator on a 1995 Oldsmobile Achieva?

Answer 1

I just did this job on my '95 Achieva about a week ago (“rear” is toward read of car; “front” is toward front of car): 1. Remove the negative cable from your battery (I usually remove the positive one, too) 2. You will need a long thin breaker bar with a 3/8-inch socket head. This is used to move the spring loaded serpentine belt tensioner. I had to make one but the better supplied auto stores have them. The square socket head goes into a square hole in the tensioner. Once you have the square head firmly seated in the tensioner, move your breaker bar toward the rear of the car. This will create enough slack to get the belt off the alternator pulley. Slide the belt out of the way and slowly allow the breaker bar to swing back toward the front of the car. (whew!) DON’T remove the breaker bar from the tensioner. 3. Remove the small plastic cap that covers the small screw post on the back side (away from the pulley) of the alternator. This will expose a 10 mm? nut that holds a small wire with an eyelet to the post. There are also a couple of lock washers. Don't lose these. (If you look at your new alternator, you will see the post is marked "BATT" or "BAT"). 4. Remove the bolt (15 mm head?) from the front alternator mount....this is the easy one! It threads into a “formed” shaft which is attached to a stud coming out of the engine case. Remove the nut on this stud and fully remove the formed steel shaft. 5. Take a deep breath….and maybe a drink of your favorite beverage. 6. The rear mount is the bear. A long bolt passes through the alternator mount, then though the alternator, then through a weird little bracket to which a bunch of wiring harnesses and a metal tube are all connected. There is a 13? mm nut on the back of this collection, and it is hard to reach because of the plastic bracket. I got to this nut via a long set of socket extensions and a u-joint extension; long enough to bypass the obstructions in the way. 7. There is also a formed (bent) metal bracket that this above assembly attaches to and is fastened at the back of the alternator. Remove the nut that attaches it to the alternator. Don’t drop any of these little fasteners! I usually stuff a rag beneath where I’m working to catch these little critters in case I drop one! (Whew!) 8. OK, the alternator should now be loose enough to carefully rotate it out of the mounting area and thus allow you to remove the electrical connections. 9. Lift it out of the way. Note that there are a couple of other unrelated electrical connections that may be in your way as you try and remove the fasteners from the back of the alternator. Disconnect them to give yourself some extra room….just remember to re-connect them! 10. Like they say in the books: “Installation is the reverse of removal” and essentially that’s true. Just take your time and work carefully. Remember the small wire to the alternator post labeled “BATT”. The nut the end of the rear mount bolt is a real pain to get started since it’s one of those self-locking nuts and is tight when started. 11. Once the alternator is installed, the breaker bar can be moved toward the rear of the car to allow enough belt slack to slip it over the alternator pulley. Now slowly release the breaker bar to allow the tensioner to create…..well, tension! Remove breaker bar. 12. Reconnect the battery. After I had the whole job done, I fired up the car and the alternator gauge still read low…..Guess who forgot to reconnect the main wiring harness plug to the alternator socket!?! Ok…one more time….. All said and done, the entire job (even with the re-connection just mentioned!) took about an hour and a half. Good luck!!