Need to ID a correct Alternator for a 69

[RT Dreamin]

Hey all! Hoping someone out there can help me out. The alternator on my ‘69 charger is on its last leg. What’s on the car is a round back double groove pulley, the car is an AC car and a true RT. I’m looking to buy a new alternator and I’m finding that they all seem to be square backs. My question is what did the 69 440 come with originally? A square back alternator or a round back? Does it matter? Is my assumption that they were 60 amp correct?

 

[RJRENTON]

Hey all! Hoping someone out there can help me out. The alternator on my ‘69 charger is on its last leg. What’s on the car is a round back double groove pulley, the car is an AC car and a true RT. I’m looking to buy a new alternator and I’m finding that they all seem to be square backs. My question is what did the 69 440 come with originally? A square back alternator or a round back? Does it matter? Is my assumption that they were 60 amp correct?

The origional alternator for a 1969 A/C equipped vehicle was a round back 46 amp unit with a single field wire connection and a mechanical voltage regulator.
The difference between round back and square back designs is the square back design has a higher amp output, usually, and a two wire field connection and a electronic voltage regulator.
Most rebuilt units are modified to be compatible on either system but require close attention to the field voltage connection as if installed on a one field car, one field will need grounded. PAY CLOSE ATTENTION TO THE FIELD CONNECTIONS IF CONSIDERING A REBUILT SQUARE BACK ALTERNATOR.
There have been many threads posted regarding this subject. Additionally pay close attention to the sheave belt alignment as it my be slightly different between your present alternator and the replacement unit.
BOB RENTON

 

[WileERobby]

Why buy a new alternator ? Get your original rebuilt.

 

[dadsbee]

Do you not have an alternator/starter rebuilder, mom and pop, shop in your town. We still have one where I can take most any electrical motor, alternator, etc and have it rebuilt properly and for a very fair price.

 

[RJRENTON]

I forgot to include this info as well.....get your origional unit rebuilt by local rebuilder....and it will fit and function as when it was when new....I concur with the other gentlemen.
BOB RENTON

 

[RT Dreamin]

I forgot to include this info as well.....get your origional unit rebuilt by local rebuilder....and it will fit and function as when it was when new....I concur with the other gentlemen.
BOB RENTON

Problem is, I’m not sure the one on there is correct, the pulley also looks different than what I have been seeing in pics of rlund backs as “original”. What’s on there is flat but when I see something that is supposed to be “original” the pulley has the center “horn” or “nose” that comes out and seems to be a little narrower in diameter. I also need new belts, the ones on there are old and fried. Classic industries has belts that are Chrysler authentic reproduction certified so I’m hoping that will be correct, but then go back to wondering which pulley is correct as well.
PS- the one that did come on the car seized up and the temp one that matched up (picked up from a friend with parts buckets) is the one on its last leg

 

[RJRENTON]

Problem is, I’m not sure the one on there is correct, the pulley also looks different than what I have been seeing in pics of rlund backs as “original”. What’s on there is flat but when I see something that is supposed to be “original” the pulley has the center “horn” or “nose” that comes out and seems to be a little narrower in diameter. I also need new belts, the ones on there are old and fried. Classic industries has belts that are Chrysler authentic reproduction certified so I’m hoping that will be correct, but then go back to wondering which pulley is correct as well.
PS- the one that did come on the car seized up and the temp one that matched up (picked up from a friend with parts buckets) is the one on its last leg

Please take a few pix of what you have now. Also the part number and amps is stamped on the top surface near where the output wire is connected. REMEMBER TO DISCONNECT THE BATTERY B4 DISCONNECTING ANY ALTERNAOR WIRES. The physical difference between the two alternators is significant. The difference in the sheaves is diameter, belt contact angle (flank) and how its attached...it's pressed on without a key. Look for the MOPAR part number....unless the unit has been replaced by a previous owner. PIX = 1000 words..
BOB RENTON
.

 

[lewtot184]

look for a date cast into the housing and see if fits with the date the car was built.

 

[RJRENTON]

look for a date cast into the housing and see if fits with the date the car was built.

The actual date code is stamped into the housing near the part number for the assembly. There will be a little clock face identification marks, with little dots cast in...this is the date that the CASTING was made...which USUALLY (but not always).proceeds the assembly build date....ALL assembly build dates proceed or are b4 the vehicles assembly date....just thought you might like to know....
BOB RENTON

 

[REB6PK]

A great alternator and starter rebuilding service is Almost NOS in WI.
They restore alternators and starters for gold certified cars and they have always been spot on.

 

[Demonic]

I'm not sure if Almost NOS is still around. I thought they were old school - no website, no social media?

 

[REB6PK]

They are still around.
Call Richard Berlisk at 262-844-2111