S-Series Alternator Replacement

[wolfman]

Saturn “S” Series alternator replacement.
The alternator is located on the firewall side of the engine below the power steering pump. You DO NOT need to remove the power steering pump to change it. Proceed as follows..

You’ll Need:
Set of jackstands and a jack
Set of metric wrenches and sockets (6 point sockets recommended)
Small blade screw driver and a pair of pliers (needle nose preferred)



Disconnect the negative battery cable.

Raise the car and support it with jackstands. DO NOT get under a car supported by a jack alone! (This CAN be accomplished with just the passenger side off the ground, but it is easier if you raise the entire front.)

Remove the passenger side wheel

Remove the inner plastic splash shield. (The small plastic “rivets” are removed by prying out the CENTER portion FIRST, then pulling out the larger outer portion. Your small screw driver and needlenose pliers can accomplish this with a little patience.)

Place a box end wrench on the tensioner pulley bolt and turn it as if you re trying to TIGHTEN it to relieve the tension on the belt. HOLD IT THERE and slip the belt off the crankshaft pulley, then release the tensioner and remove the now loose belt from the other pulleys and car.

There is a 13mm head bolt on the top of the alternator below the power steering pump, remove it, it's the top anchor point for the alt. It can be a challange to reach, some find it easier from above, some from below,..your choice.

From BELOW, Remove the plastic shield from the alt if it has one. Unplug the connector from the alt. And undo the 10mm nut holding the power output wire to the back of the alternator slip the wire off the alt. stud.

Remove the 13mm nut and bolt head lower alt pivot bolt and nut.

Remove the alt from the engine and move it out through the opening in the wheel well.

Install in reverse.

NOTES for reinstallation…
Attach the alternator to the engine with the lower bolt BEFORE you attach the wires to make it easier and avoid pinching/straining them.
When attaching the power output wire to the alternator be VERY CAREFUL nut to overtighten it or flex the alt. mounting stud. It has a plastic insulator that can be broken this way rendering the “new” alternator useless.
When installing the belt, there is a diagram on the upper radiator support showing how it should be routed. If, when you release the tensioner the belt is not TIGHT, you have done something wrong, recheck it. I have always found it easier to install the belt on the crankshaft pulley LAST while holding the tensioner released….
Before reinstalling the belt, it is a good idea to clean all the other pulleys with some spray cleaner and an old rag to help the belt grip better.
The plastic rivets holding the splash shields on are reinstalled by putting the LARGER OUTER portion in FIRST then the smaller inner portion. If you destroy one or more removing them, they are available at most autoparts stores by the bagfull.

[TedL]

NAPA P/N 665-2388 will work fine as a replacement for the splash shield retainers.

Also, one or both of the splash shields have "christmas tree" retainers molded right into them. If it breaks off, just drill a hole through the shield at the same spot and use an extra of the two part retainers in its place. The hole it goes into will already be there.:yes:

[David 93 SL2m]

Originally posted by wolfman
Place a box end wrench on the tensioner pulley bolt and turn it as if you re trying to TIGHTEN it to relieve the tension on the belt. HOLD IT THERE and slip the belt off the crankshaft pulley, then release the tensioner and remove the now loose belt from the other pulleys and car.The size needed for this is 14mm.

[ym42]

Well, I hate to correct Wolfman, but... the upper bolt is not 13mm, but 10mm, smaller than the lower 13mm but ;) The upper bolt is a little pain to remove, but it CAN be done with either a ratchet or a box-end.

[ym42]

Strange, on my SL1 it is 10mm, on SL with no p/s it is 13mm. So I guess Mr Wolfman is not wrong, but size varies.

[vrg3]

Thanks for the really helpful writeup, wolfman.

To add another data point, the upper bolt was 13mm on the 94 SL2 I just did the job on.

Some things I have to add:

- The plastic shield on the alternator is held in place by a bolt with a 10mm head almost directly above the electrical harness connector. Look at the back of the new alternator to see where the bolt threads in to get some idea of what to feel for.

- The diagram on the upper radiator support also points out which pulley is the tensioner, in case you're unsure.

- There's very little room to get a wrench onto the tensioner pulley bolt. If the wrench has any kind of offset on it you're unlikely to be able to fit it on. I had a 14mm combination wrench with an offset closed end and a flat open end. I tied a rope through the closed end and slid the open end onto the pulley, with the wrench horizontal and the open part facing the front of the car (try to visualize it). This made it very easy to remove and install the belt; I pulled upward on the rope with one hand and worked the belt on or off the A/C compressor pulley with the other hand. This may vary depending on the accessories your car has.

- When connecting the heavy wire to the alternator, it should be routed so it comes downward off the alternator. That way the plastic shield fits on better. It's not a bad idea to smear some silicone dielectric grease on afterwards to go under the boot.

- It's a good idea to smear some dielectric grease into the harness connector before connecting it as well.

- The harness connector is held in place with a little tab that you lift off with a flat-blade screwdriver; look at the receptacle on the new alternator to get some idea where the tab clips on.

- Be very careful not to overtighten the battery terminal; they put a 5/16" head on a 3/8" bolt to discourage you from overtorquing it.

- Make sure your battery is fully charged before starting the car with the new alternator. Even if you think your battery is okay it's probably a good idea to give it a good charge anyway; dead or dying alternators tend to result in discharged batteries of course, and flat batteries are very hard on alternators and voltage regulators.

[M.Nguyen]

If calling around, it's the alt with an external fan...i guess AZ had one with an internal fan available. Stay with AZ, because you get a lifetime waranty, as opposed to the 1 year of H.O. alts. They all poop out because there's little airflow back behind the engine, and it gets hot fast.

[Luke]

Fm vrg
Thanks for the really helpful writeup, wolfman.

To add another data point, the upper bolt was 13mm on the 94 SL2 I just did the job on.

Some things I have to add:...........

And thank YOU for the added detailed input......

Copy and Paste...:D

[jasonpopnc]

I had one heck of a time removing the wire that connects to the starter. What I did was remove the wire from the starter side. Once out, i noticed that the alternator connection was way over tightened and the stud rotated with every turn of the wrench. Luckily there was a wrench flat near the base of the stud that I was able to use to the the nut off.

[dw97sc1]

I have to try again tomorrow with a different wrench I guess.
Thanks for having this site.

[dw97sc1]

All changed thanks for the how to.

~Dave Woodard

[SpeedPlayer 97sl2]

I had a heck of a time actually getting the alternator out of the car. It's a tight squeeze in there. I finally found the trick to getting out from it's original location. Just rotate the alternator upside down such that the holes at the bottom of the alt (where the 13 mm bottom nut and bolt thread through) are at the top. This somehow gives you enough room to slide it out. I couldn't get the new alt in by any other method either. Had to flip the new alt upside down again, and then rotate it right side up once inside. Not sure if this would apply to the space available in other people's cars, but I had some restriction from various hoses and cables that required me to do this.

[Luke]

SpeedPlayer
Thank you
Copy & Paste...:D

[DiscoverOrchids]

THANK YOU!!! I just bought a 1997 SL1 and on the way home from the lot the alternator went out. Figures!

It was at night no less so, about 8 miles from home that was it...... Dead on the road. I had my wife bring me the battery from our 88 buick wagon and got home. It took me a little while to find this post but I am so greatful I did. I was able to figure out how to do the job before I ever looked at the compartment in the daylight (after the alternator was bought). It was so nice to also know EXACTLY what size wrench to use in each place. No guess work! Had I not read this post the job would have been frustrating and I would have had some choice words for the car. Nothing like our Land Rover where the alternator is right on top of the engine and only two bolts and your done but it was made much easier knowning the "way" to do it ahead of time. This time it took me about an hour but I know the next will not be long (assuming I need to replace it in a few years again). It gave me JUST enough time to go replace the two front tires that were bald before they closed shop.

Thanks again!
Kevin

[sierrap615]

good to hear discover, congrats on the purchase, hope we can help you in the future too.

[irish56]

Originally posted by wolfman
There is a 13mm head bolt on the top of the alternator below the power steering pump, remove it, it's the top anchor point for the alt. It can be a challange to reach, some find it easier from above, some from below,..your choice...

I had to replace the alternator in the '95 SL1 today. Thanks to you guys and this thread, it was pretty easy, EXCEPT for the top alternator bolt. I could not reach it from above or below because of the subframe rail running right next to it. So I unbolted the top engine mount, then raised the engine about 1.5" using a floor jack under the oil pan with a piece of wood to distribute the load. Then I could easily access the bolt from the top with a deep-well 13mm socket.

[RichStep]

Another CRITICAL DETAIL that was not mentioned is make sure the lower bolt/nut is well snug. I've had these cars come in with the mount (an important piece connected to the engine block) snapped of from the bolt being too loose. The vibration finally broke the mount clean off the block! And now because the last guy who changed their generator assembly didn't tighen the lower bolt...I had to drop a new block!

[The Budman]

Great tips! Out and replaced in 40 mins.

[bgates2b]

Excellent tips!!!!! It took me a NET of 20 minutes to change. I say NET because I had a bit of a fiasco.

I bought one of those black 140 amp Powermaster alternators (they dyno it, mine is 89 amps at idle, 147 amps @ 2000 RPM :D ).

The old one came out easy thanks to the instructions. The new one did not fit though. The bushing on the pivot joint was too thick. I was able to punch the bushing out of the old alternator, but I could not get it out of the new one. So, I had to put the old alternator back on, button her up, go get a thick enough punch to get the bushing out, come back, take the alternator off, punch out both bushings and c-clamp the old bushing into the new alternator. Once done, it fit like a glove!!!!!!!

Now, for those of you that are debating the upper bolt. I am putting it on a 94 SL2. I spotted the previous post saying it was a 13mm bolt so that's what I brought out to the car. I tried the 13 mm and it was too big. I went and got a 10mm socket and it fit. I took out the bolt and I realized.....#%@^&%. The 10mm bolt belongs to the power steering mount, not the alternator mount. I tightened it back up, pulled out the 13 mm, felt for the bolt, found it and unscrewed it.

So now I wonder if those with 10mm bolts are removing the power steering mount bolts

[David 93 SL2m]

The new one did not fit though. The bushing on the pivot joint was too thick. I was able to punch the bushing out of the old alternator, but I could not get it out of the new one. So, I had to put the old alternator back on, button her up, go get a thick enough punch to get the bushing out, come back, take the alternator off, punch out both bushings and c-clamp the old bushing into the new alternator. Once done, it fit like a glove!!!!!!!If the alternator bushing thing that gave you a hassle looked like this, then I had the same exact problem. My solution was to punch it out of the hole and jam it back in but from the other side. Without pictures this probably does not make much sense. I would have photographed this but I was delayed and irritated by this point so the camera was the last thing on my mind. But I saved this part from the old alternator to remind myself for the next time! :hothead:

[bgates2b]

Originally posted by David 93 SL2m
My solution was to punch it out of the hole and jam it back in but from the other side.

Yep, that's the bushing. I thought about turning it around but I was not sure if it would cause a problem with the alternator casing rubbing up against the mount. I figured the thick part acts as a washer of sorts.

I am going to E-mail Powermaster to make them aware of this problem though. Otherwise, I have bright lights at night and no antilock light coming on

[Roadmaster]

Replaced the alternator on my 94 SW1 and it was easy with these tips. The biggest hassel was the top bolt under the power steering pulley but I managed to get my gorilla hands in there and the bolt started after several attempts. My alt light (battery) never stayed on and would occassionaly go on and off while going down the road and when under a load such as the AC. I knew it was only a matter of time and replaced it he next day rather than out guess when it would finally take a dump and strand me. This is such a great site with great people who care!

[Alex74cpa]

[FONT=Arial]Great write-up Wolfman. Just a few things I wanted to add.

The Delco CS-130 alternator used on the earlier S-series (1991 to 1998??) have a history of premature failure due to extreme overheating of the diodes and rear bearing. The poor cooling is due to the fact that they're small compared to their power output and can't get rid of the heat very well. The good news is there's a solution. Quick Start makes an "Iceberg" kit that has a redesigned case with more cooling fins, larger rear bearing, and heavier diodes (50 amp instead of the stock 35). The alternator is still good in my '93 SL2, but i'm pulling the engine for a clutch job - I'm going to install the alternator kit just to be safe. You can get the kit at www.alternatorparts.com - I think it's about $50.

There's also a high output version of the kit. I'm going to stay away from it beacuse I figure the extra amperage will generate more heat and strain the diodes more. Besides, 85 amps isn't too shabby.

One final note: my brother had a Cavalier with a CS-130 and over the course of the 7 years he owned it, her replaced the alternator 6 times! It was a good car other than the alternator. :dizzy:

[dieseljack]

[FONT=Arial]Great write-up Wolfman. Just a few things I wanted to add.

There's also a high output version of the kit. I'm going to stay away from it beacuse I figure the extra amperage will generate more heat and strain the diodes more. Besides, 85 amps isn't too shabby.

One final note: my brother had a Cavalier with a CS-130 and over the course of the 7 years he owned it, her replaced the alternator 6 times! It was a good car other than the alternator. :dizzy:

I'm a little puzzled. The standard output of that alternator should be 90 amps as it is. As far as heat is concerned, I had a CS-130 in an '88 Fiero with mid-engine underhood temperatures that would bake lasagna. In almost 200,000 miles of operation, it never quit. Same for the one in my '95 SW1, and that puppy just hit 364,000.

I think your brother's unfortunate experiences were likely due to defective aftermarkets, or improper installation.

[sierrap615]

91-94 CS130 85 amps
95-97 CS130 96 amps
98-02(and a small handful of 97s) CS121D 90 amps

on the fiero i bet it aleast had some airflow, on saturns there is no real airflow to the alternator, its next to the exhaust and starter, and by some miricle the valve cover always leaks just above the alternator. if your alternator has 364k miles i think thats a record.

[David 93 SL2m]

My original alternator lasted between 11/14/1992 and 08/08/2003 which is 10 years, 8 months, and 26 days. Mine did not have a "shield" as noted by other Saturn owners and by the Chilton's manual. Maybe my Saturn dealer took it off when my car was delivered from the factory as a precaution to trapping heat and shortening the life of the alternator? Maybe a factory worker forgot to put it? I don't know but after reading posts at SaturnFans it seems that most - but not all - S-Series alternators tend to last 7 or 8 years. Perhaps my alternator lasted a relatively long time because the shield was missing...

On 08/16/2003 I replaced my alternator with a rebuilt unit from NAPA, part number RSE2134591, cost $80. I don't know how many amps it produces. It has been working fine (as of this post it has been in use for 1 year, 9 months, and 24 days). I examined the original alternator and the replacement alternator; to the best of my knowledge they are identical except one was very dirty and one was very clean. I thought about picking up a shield for my alternator several times to keep the dirt and various liquids off it but chose not to as it might trap heat and lead to premature failure.

http://home.comcast.net/~David93SL2/Alternator-swap.jpg

[Lurker1999]

I just replaced my alternator following the great instructions in this thread and had similar problems with the top bolt. However using the new alternator as a rough guide I was able to estimate its approximate position which made it far easier to spot.

One thing that wasn't initially clear to me was that the bottom bolt has a bolt and a nut so you'll need two 13mm somethings (i.e. socket and wrench) otherwise you'll just be spinning the bolt.

Whoever put my old alternator on cranked down on the mounting stud so I had to break the plastic on the old alternator off to allow me to use a 14mm wrench to hold the bolt as I used a 10mm wrench to turn the nut.

The battery harness connector will fit under the plastic shield but there is some type of other electrical line running a little near the top of the alternator. That won't fit under the shield which stumped me a bit initially until I pushed it out of the way allowing the shield fit snugly on the alternator (and allowing me to find the bolt hole at last).

Keep a headlamp in your toolkit. Unless you're working in glaring bright sunlight you'll want the extra spot-on light to work under the car.