Round back or Square back alternator?

[koosh]

On my 69 Bee… i have what looks original round back alternator, with 2 wires. Can this be replaced with a square back that has more wire terminals on it? Pics attached show my alternator, and the electronic pieces on the firewall which I don’t know would need changing with square back?
Thanks

 

[72RoadrunnerGTX]

Yes, you can run a later dual isolated field alternator on a ’69 and earlier application, just ground one field terminal. No technical reason to replace the existing mechanical regulator if it’s working as it should. However upgrading to the later electronic regulator is fairly easy to do.

 

[koosh]

Yes, you can run a later dual isolated field alternator on a ’69 and earlier application, just ground one field terminal. No technical reason to replace the existing mechanical regulator if it’s working as it should. However upgrading to the later electronic regulator is fairly easy to do.

So run a wire from field terminal to a ground spot?
Which firewall piece is the mechanical regulator? Lol… ready don’t know this stuff

 

[Tony Tee]

The black box .

 

[72RoadrunnerGTX]

Yep, run a wire from one field terminal to the alternator case, connect the single original field wire to the other. The black device in you pic is an original style mechanical regulator.

 

[R413]

Why change it? What is the reasoning? Why not leave it.

 

[koosh]

Why change it? What is the reasoning? Why not leave it.

Its growling, and a buddy has a free square back i can have

 

[koosh]

Yep, run a wire from one field terminal to the alternator case, connect the single original field wire to the other. The black device in you pic is an original style mechanical regulator.

Ok. So keep original regulator then?

 

[Jerry Hall]

When you change out the alternator, wire everything just like it is now. There will be a place on the square back alternator that is not used. That is the terminal you need to ground.

 

[RJRENTON]

W

On my 69 Bee… i have what looks original round back alternator, with 2 wires. Can this be replaced with a square back that has more wire terminals on it? Pics attached show my alternator, and the electronic pieces on the firewall which I don’t know would need changing with square back?
Thanks

View attachment 1638524

View attachment 1638525

View attachment 1638526

WHY DO YOU WANT TO CHANGE IT (or think you need to change it)?? Is it still functioning adequately?? Or are you just looking for something to do? "If it's not broke, don't fix it" or do the rest of your "buddies" say you need to change it....for unknown reasons......
BOB RENTON

 

[1967coronet]

Bob in post # 7 he explains the reason for the swap.

 

[RJRENTON]

Bob in post # 7 he explains the reason for the swap.

Rather than go to all the related issues/problems, of changing to the isolated field unit, why not just rebuild what you have. Its likely the front bearing....a #6203 double shielded, pre lubricated and sealed single row ball bearing. Its easy to change. The manufacturer can be: SKF, TORRINGTON, RBC, NTN, etc.. Replace the brushes when apart. Add a dollup of synthetic grease to the rear caged needle bearing. The FSM shows you EXACTLY how to service the alternator. ......just my opinion of course.....and DON'T trade it in for a "rebuilt" auto parts store unit...
BOB RENTON

 

[koosh]

Rather than go to all the related issues/problems, of changing to the isolated field unit, why not just rebuild what you have. Its likely the front bearing....a #6203 double shielded, pre lubricated and sealed single row ball bearing. Its easy to change. The manufacturer can be: SKF, TORRINGTON, RBC, NTN, etc.. Replace the brushes when apart. Add a dollup of synthetic grease to the rear caged needle bearing. The FSM shows you EXACTLY how to service the alternator. ......just my opinion of course.....and DON'T trade it in for a "rebuilt" auto parts store unit...
BOB RENTON

While i can appreciate your opinion, slapping in a free new alternator makes more sense to me than rebuilding the relic. (as long as new one will work)

 

[RJRENTON]

While i can appreciate your opinion, slapping in a free new alternator makes more sense to me than rebuilding the relic. (as long as new one will work)

How do you know the "freebe" offered will work or have bearing issues as well. You will also need to install the corresponding voltage regulator in lieu of the one presently in service. ......too many "experts" involved.....
BOB RENTON

 

[Nacho-RT74]

Unless the squareback unit is able and proveed to provide more amps to get more juice from it, I can’t see a reason for an alt replacement. Fix/service an alt is easy and cheap, specially the bearings.

Now, if you were to upgrade the full system with the matching elect reg which is proveed to provide better performance, (specially having elect ign) that’s a diff story. But these are just personal opinions.

However as mentioned, grounding one of the alt fields will make the job

 

[Bird 426]

Install the square back if you must, but rebuild your round back and reinstall it when done. Oh, and nothing is free.

 

[koosh]

Lol

 

[Charlie71rt]

Is there a way to remove the pulley to change the front bearing without a specific puller?

 

[Nacho-RT74]

I have been to remove the pulley from my alts with a regular “two arms” universal puller grabbing from sides of pulley, but just able to do it if they isn’t too tight, because if pulley is stuck on shaft will get bent.

It happened once to me.