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Hi,
I have an 89 SC that has a bad alternator. I have an OEM spare that I had professionally rebuilt to replace it with. My car also has AC. Is there a good write up somewhere, preferably with pictures, on how to do the replacement? Everything I find is for NA models, and/or without AC. I was waiting on a friend to help me but he has been nonstop too busy. In debating taking it to a shop but dont want to pay top dollar for less than top notch work. My dad is trying to convince me to tackle it myself since I recently replaced the entire suspension on my own. But wiring and belts tend to intimidate me.
 

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1. Are you sure that it is the alternator that is bad, and not the regulator? On the SC cars, they are separate units.
2. Disconnect the battery before you touch it.
3. What is the issue? Is it a difficult access? The charging wire bolts to a stud, and the rest of the wires unplug. The belt just goes around the pulleys.
 

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Discussion Starter #3
1. Are you sure that it is the alternator that is bad, and not the regulator? On the SC cars, they are separate units.
2. Disconnect the battery before you touch it.
3. What is the issue? Is it a difficult access? The charging wire bolts to a stud, and the rest of the wires unplug. The belt just goes around the pulleys.
1. Definitely a bad alternator. I had tried replacing the regulator first.
2. Of course
3. Yes, difficult access. It is on the opposite side of the engine as the NA alternator.
 

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Hi gxelover, I just replaced my second alternator on my '89SC with AC. Currently at 308K on the original engine. It's sandwiched in there between the distributor and AC as you know, but there is a trick. It can come out the side vent opening, but you have to be patient with it. Like rmeller said the wiring and belt is not difficult. Loosen the belt tensioner at the bolt in its bracket from underneath. You need to take off that plastic dust cover from under the motor if you still have one. There are two tensioners, pick the correct one, not the SC belt tensioner. Wiring is a single round plug on a ~6" pigtail that wraps around the outside of the alternator so it can be accessed from above and a thick charging wire that comes off a copper post with a nut that is sticking out the back of the alternator. You get to that charging wire from underneath. The alternator mounts to its bracket at two "ears" on the allternator body. One long bolt with a nut on the bottom and one short bolt on top that threads right into the bracket from the front of the alternator. You will see it through the vent hole. What I do is unbolt the vent fan and hang it out of the way with a wire coat hanger. Remove the plastic scoop with its two screws on the outside. You will see the alternator through the hole. The plastic shroud inside the body stays mounted to the body, just remove the fan. If the alternator is caked with oil/dirt from past distributor o-ring leaks, clean it first to clear the bracket mounting points so it can slide off the bracket. Loosen both bolts and remove the top one so the alternator can pivot on the long bolt. Spray WD40 or similar on the bracket if it doesn't easily pivot at first. You can also carefully pry between the alternator body and the bracket with a large screwdriver if it is stubborn. Once the alternator is loose from the bracket you need to orient it correctly so it fits through the vent hole. It will come out. A second person helping from above would be good, but I have done it twice by myself. Re-assemble in reverse order.
 
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