Alternator Rebuild - Something 4 U to consider?

[72LT1Steve]

I just recently ordered and received the rebuild kits for my original #'s matching alternator. I had been thinking about going through it since last year & finally got off my rear end and obtained the parts to do so. The alternator has/had some 81,000 miles on it.

I'm glad I did do something finally, because when I tore the alternator apart I found the the bearings basically worn out and very dry. The front bearing had it's casing crumbling (basically a sealed bearing) & no grease there what-so-ever. The rear had minimal grease & was showing it's age.

Assuming you have your original alternator & plan on keeping it & not just replacing it when dead, have you given any thought to at least grease the bearings inside at a minimum?? I'm glad I tore into mine and rebuilt it for two reasons:

1). I'm sure the alternator would have failed in the very near future. &

2). It gave me the opportunity to thoroughly clean the case and other parts of built up decades of grime. It now looks factory fresh and clean

Just something to think about

Steve

 

[mvftw]

Where did you get the kit from? Mine is also factory with 92K on it. I was thinking of doing the same...

 

[SwaveDave]

Since my vette isnt all original, i opted for a chrome 100 amp TuffStuff Alternator. Just put it on this morning. The factory alternators were real low output ; 63 amps for my BB . Something i do periodically, is , shoot some compressed air thru the air openings of the alternator to blow out dust and debris from the road. I checked with an alternator manufacturer and they said its okay to do that.

Since alternators are relatively inexpensive, i shall probably replace them every 5 or 6 years just for safetys sake. I change batteries every 3 years too.


Dave

 

[Jack]

Early chev alts are easy to get apart & cheap to get parts for ... any parts house ... also cheap to buy a rebuilt one $25-$40. Not so with late GM alts ... my little 97 GMC truck had a noisy but strong alt. They're also very difficult to get apart. While I replaced the water pump recently, I pulled the alt and took it to a shop & had them rebuild ... $75 ... compare that to about $200 Advance-Autozone wants for same over-the-counter rebuilt late GM alt. I dunno any way for routine maintenance other than periodically pulling alt apart & grease/replace bearings ... that's what I'd do if original. My 71 is not so I have a backup $25 rebuilt alt.
JACK:gap

 

[72LT1Steve]

Where did you get the kit from? Mine is also factory with 92K on it. I was thinking of doing the same...

mvftw: I ordered my bearing kit & general alternator repair kit from from J.C. Whitney. $8.99 & $15.99 respectively.

Steve

 

[hdflh67]

I had my matching # alternator professionally rebuilt locally for about $50. They were able to double the amp output while retaining the original casings, etc. Cleaned and painted to original appearance. Well worth the $$$ to know everything was done correctly and now has a warranty!

 

[crebo]

hdflh67


Want to clean and service my alt. You also said you painted it to original appearance. Not being funny but what type of paint did you use? Cast or is it cool to paint it any color?
Thanks
Crebo

 

[Eddie 70]

My car is far from stock and I rebuilt my alternator too. I took my alternator all apart and sandblasted the case. Then I took it to my powdercoater and had it powdercoated black. Then when was prepping the windings, I painted the exposed portion red. Now my alternator looks as good as any from Summit and only cost a few bucks to get there. It has new bearings and new brushes. All is great there now.

 

[a69vette]

Question: Was your alt. making any noise before you decided to rebuild? I thought I had a loose belt, but it appears that the sound is coming from the alt. Does this mean a bearing going bad? Could you please describe the rebuild process in a little more detail?
Thanks,
Rick

 

[72LT1Steve]

Question: Was your alt. making any noise before you decided to rebuild? I thought I had a loose belt, but it appears that the sound is coming from the alt. Does this mean a bearing going bad? Could you please describe the rebuild process in a little more detail?
Thanks,
Rick

Rick: No, my alternator wasn't making any noise that I could tell. I just figured it was in need of some attention since a typical alternator seems to last 60,000 + miles or so and my car is at around 81,000.
If your hearing some noise at your alternator, I would hazard to guess that at least your bearings are dry. Just like wheel bearings, if not regreased they'll make noise & eventually fail.
The rebuild is quite simple (at least I thought it was). The rebuild alternator kit and bearing kit both came with instruction sheets outlining the process. Just basic tools are needed, along with oil degreaser & electrical parts cleaner. A bench vise, and metal cleaner and/or a wire brush.

Here are some of the very basic rebuild steps:

1). Disconnect battery and remove alternator from car.

2). On lower side, out of sight, score alt. case with line (for re-assembly purposes)

3). If alt. original, most likely only 4 screws hold it together. Remove them & seperate halves. Provided rebuild instructions are now followed (only four replacement parts were in my rebuild kit. Bearing kit is seperate w/two bearings).

4). With case seperated you can see the rear bearing and see how bad or good it is. (I'd replace both bearings regardless anyway)

5). Front bearing is under the rotating assembly and this is where the vise comes in since you have to clamp the assembly tight so the front securing nut can be loosened.
IMPORTANT!! - DO NOT clamp metal rotating assembly with the metal vise without protecting the metal rotating assembly. I cut a section of a old rubber serpentine belt that came off of my Jeep Cherokee that worked great for that.

6). The nut holding the alt. fan is removed which frees the front case from the rotating assembly. This is where the front bearing is located on the underside of the case. There's a cover plate w/3 screws holding it on, remove the screws and the bearing is exposed. The bearings are gently (don't want to damage the case) tapped/knocked out & the new ones tapped into place (I added additional grease under the front securing cover and inside the rear bearing itself).

7). Once the case and other related parts are cleaned, the alt. is re-assembled (this is where the line marks on the case come into play) then re-installed onto the car.

Like a I said at the beginning, this is just a basic outline. The instructions spell it out quite well (mine also had diagrams). There were not a lot of parts & pieces to worry about. I spent more time cleaning the darned thing of grease and grime than I did in the actual rebuild of the alt. itself. The cleaning was both inside and outside the case, with a lot of it being inside the case!

Hope this helps.

Steve

 

[a69vette]

Those a great instructions. This will be my next project.
Thanks for the help.
Rick

 

[72LT1Steve]

Those a great instructions. This will be my next project.
Thanks for the help.
Rick

My pleasure.....Good luck! Steve