3.2 alternator recomendation
 

Hi, Looks like my alternator is needing to be replaced. I just retired and want to learn how to do more wrenching than filter and belt changes and brake flushes. Here's my chance as the only way to learn is to just do it. After reading the great advice on this forum looks like the trickiest part may be getting the fan off?
My question today is - there's several alternators listed at Pelican. What's the best one to get for the money?

Thanks,

John, I just went through the same thing with my 1986 3.2. I purchased the Bosch replacement alternator from Pelican but it didn't work after I installed it. I assumed I had a ground problem or a wire broken so I started a thread here and got some tremendous help from this community. I traced wires all over the car and spent nearly two days trying to figure out the problem. I could tell that some of the guys here were serious experts with 911 wiring but we couldn't figure out what the problem was.

After eliminating absolutely everything else it came down the that replacement alternator itself. I ordered a $30 Marchal voltage regulator (from Pelican) to replace the one on the Bosch unit and it's been working perfect ever since. To be honest, I wonder now if that's what was wrong with my original unit. I didn't try it but I wouldn't be a bit surprised. I would definitely try that first. Once you get the alternator out it only takes 2 screws to replace the voltage regulator. The whole job isn't very difficult at all. It's a little tricky getting your hand in behind that cover and you need to make sure the orientation of the fins go back on the alternator correctly but other than that it shouldn't take more than 2 - 3 hours for a first timer. Someone who's experienced could probably do it in 30 min.

John, actually I need to clarify my recommendation... if your problem is from the alternator not charging then try the voltage regulator first but if your problem is from bearing whine then you'll need to get another alternator. From what I understand (and I may be speaking out of turn here) it's actually pretty rare for the copper windings in an alternator like this to go bad. They're pretty heavy duty and nothing actually touches. I think most of the time the electrical problems are a result of a bad voltage regulator but I have limited experience on this and I'm sure some of the other guys here on the forum are much more knowledgeable about this.

Take a picture of those air deflection fins before removing the unit. Seems like that was the only thing that slowed me down when I replaced the alt in my '88.

Thanks supersignman. I should have mentioned I do get bearing whine and after a dead battery I measured the voltage. Mostly I get 12.3 volts which is just the battery with a few 14.3s and one 16. That's why I was thinking new alternator to eliminate the whine. It is 30 years old.

I would recommend you take your old alternator to a local rebuild shop. They can change the bearings, and any parts that are worn, and make it as good as new for cheap. I did just that 15 years ago, and I have had no issues at all.

Hi John W.- I've been really pleased with the Bosch AL-401-X Reman from our host. Here's my story...

https://forums.pelicanparts.com/porsche-911-technical-forum/1034827-1986-alternator-replacement-rumbling-noise-now-gone-hidden-bolt-c-plate.html

Personally I always take my old unit to local rebuilder and bench test it before installation. Rebuilders are a dying breed. But worth it if one is near you. Store bought remans have a high failure rate. Even of they offer a lifetime warranty YOU pay the labor.

Same here. I took my El Camino alternator in to a local shop expecting to have to come back to get it. They jumped on it right away, and replaced the bearings, and diodes and brushes. Tested it and handed it back in 25 minutes.

John,
I would either decide if you want to do the the work yourself, take off and have it rebuilt or just replace the whole alternator.

I just finished replacing bearings on my 87 which was a Valeo A14N67+. I had called a local alternator shop and they had some “world pac” bearings which equals some cheap chineseium crap. I had never rebuilt one but I was mainly after the bad bearings. After opening up the alternator the brushes were good, very little wear at 56k miles. The rectifier was fine as I had no issue with voltage/charging so it was dissembling to replace bearings. In the end I spent more on some high quality SKF 6201-2RSJEM & 6303-2RSJEM bearings and a new Valeo tolerance ring to mount the rear bearings. In the end it was well worth it and will do it again when the brushes need replacing in another 50-75k miles.

I would read posts on this site, lots of good info and if your willing to look around you can get quality bearings and OEM internal parts to have a like new alternator.


CTopher

Internal voltage regulator in my Valeo went bad and boiled my battery (which until then appeared to be still working just fine after 10+ years).

Shop replaced with a Bosch reman; still working perfectly 4-5 years later when I removed it in favor of the ClassicRetrofit/WOSP unit.

The CR unit is impressive; lighter, stuffs out 14.5V at idle and roughly double the current of the late alternators the factory used thanks to the modern alternator design. Lights are noticeably brighter, and my oil pressure (and other gauges) don't tick down a notch when I switch the lights on anymore...

Running the big beefy upgraded red cable through the tin/incorporating into the motor harness was the biggest install issue. Getting the fan off was the easy part (use some lumber and drop the housing on it carefully/strategically).

For a 89, you'd use both spacers to backspace to the late fan housing - or backdate to an earlier (stronger) fan housing if desired.

Up to you what makes the most sense; could be rebuilding your original.

I used to send all our alternators to the local rebuilder. They also did starters. Cost was $75-125 and one to two days. They would always show me what was wrong and for them, it was easy peasy. I did dozens that way and always had good success.

Ctopher: how did you get the bearings out.... use a hydraulic press?

I used a old Famco arbor press but if you were careful a vise and hammer along with a set like below. I used a large socket, 36mm to catch the rear bearing and the kit below with the right size to press in the front bearing. The key is supporting the housing around the bearing, you never want to use the actual large housing as you’ll crack it. The rear one was similar with having the right size socket or the press kit to press out the bearing. The hardest part I had was finding a cross reference to the NSK bearing based on the odd number on the seal of the front bearings. The rear was a no-name Poland labeled bearing. :) In the end most all bearings are pretty basic, sized and knowing what type of seal you need. I used SKF JEM bearings which use high temp Urea grease, rated for electric motors and have 24k rpm ratings.


https://www.amazon.com/gp/product/B07CHGQCQ3/ref=ppx_yo_dt_b_asin_title_o07_s00?ie=UTF8&psc=1

http://forums.pelicanparts.com/uploa...1574298564.jpg

http://forums.pelicanparts.com/uploa...1574298564.jpg


CTopher

I, too, took my old alternator to a local rebuilt shop and they had it good as new for less than $100. It has been working great for 4+ years...

Anyone that does this make sure you are asking about the bearings they use. The local shop only had the crappy chineseium parts and didn’t carry any high end bearings.

I personally want to know that quality parts are used, thus why I did it myself.

CTopher

Thanks for the great advise. This forum has awesome members. I’m going to take the rebuild path.

When people suggest taking to the local "alternator rebuild shop", what exactly is this? I've never seen an "alternator shop". When I Google that, I don't see a single hit in my entire county. I'd have to cross state lines. Do they only fix alternators in farm areas and inner cities?

Mine is at the local auto battery shop. I wouldn’t have known but a friend told me. I would pull up local battery shop and ask or ask your local mechanic if they know.

The shop I use is almost in downtown Oklahoma City. They rebuild starters and alternators.

Sty to google "starter repair" or "alternator repair". They are a vanishing breed however. So many people have disposable cars.

Another thing to try, do you know a professional mechanic or repair shop? Call them and ask which local repair shop they like for alternator repair.