Alternator Rebuild - How to

[yel-low]

Re-installation is pretty straight forward.




Here she is in all her glory!

Just like new!

[yel-low]

Numbers time:
You have to admit after going through a whole afternoon of pulling that alternator out, cleaning, and rebuilding that one has to wonder… “Wouldn’t it have been better just to buy one already rebuilt”?

Well I bench tested the alternator after I was done hoping to see something close to what a new OEM alternator would put out. I didn’t really have high hopes considering my windings were old.

Here are my numbers:
Before: ~13.5 volts ~18-19 amps 2000 rpm
After: 14.6 volts at a steady 156.5 amps!!!!!!!!!!!!!!

I almost had a heart attack. I couldn’t believe it!!!! I had three colleagues come over and verify and everyone was just stunned. My lights are brighter, dash is well lit, and EVERYTHING seems to run better. My regulator must be pinged at its max because I am sure I could probably get much more than that.

Hope this was helpful.

[milly00]

**** man. I been looking for something this beefy for all my stereo crap. Im sure mines about to crap also. I got an estimate and they said the most could get me was a 110A Alternator. They said mine was 90A stock. I dont believe its 90 stock. Its 2000 2.5L Millenia. I was thinking 110 wasnt enough. Now, here it is. After all the shops I called about re-building my alternator they asked what kind of car and said they couldnt do it. I really need something like you got now with 156 Amps. Good Job man congrats

[Saint_]

Mine gives 100+ amp and 14.45V at most. 156A is prolly the best you can get in a sedan. Good work.

[SteveSter]

When you took those reading were you doing a full-field test and jumping the terminals on the VR? The first reading you took may have been with the battery fully charged and the VR wasnt putting out full voltage.

Very good write up, Ive done this before a couple times in class but never got around to taking pics during the process. Most people will just go rebuilt with a warranty.

[yel-low]

I load tested both alternators on a bench. Same power supply, same conditions. I was too scared to jump the VR because I had no clue how the voltage spike would have reacted and didn't want to do that with it still in the car. I would hate to fry my ECM.

The old rectifier clearly had blown didoes so that accounted for my weak output.

[Xedosman]

Very good guide! I am stumped how the perfomance could get better than stock...

For those scared of the work implied, I would like to add that in most cases a brush and bearing swap will do the trick. At least in our climate. But a fullfledged writeup is awesome

Oh, one more thing. The axle has a hexagon end; no need for an impact gun on this one. No fan of those, see

[yel-low]

This is an update:

As I strive towards continual improvements in all products I fabricate; I have now improved on my Hi-output alternator.

I have now successfully been able to hit over 210amps stable on my new alternators!!
It is a totally different beast in comparison to the one detailed in this post.
Please PM if there is any interest.

[Saint_]

Wow its gonna slow down the car when charging a (capable) battery

[yel-low]

Like I said... not for everyone. There is a tiny bit more drag but nothing drastic. After all ...none of our Millenias are drag or super street cars. I'd be surprised if you lost a hp or too from this alt. I rebuild with new bearings and such so I'm sure its drag is far better than the tired old one in our cars anyway.

This alt is for those who have multiple batteries or really pound their systems.

We are not talking permanent magnet motors here....

The old alternators were maxed out due to regulator, diode bank, and windings. I've upgraded all of them (in a new method) and its resulted in a great performer.