AJFink

After getting everything aligned on the engine pulley wise. I thought I had better get the Alternator tested. When I took it down to get it tested, the kid at the counter said that I had a 63amp alternator and was for a 455 engine and the regulator is built in and that it was bad only putting out 11.3 volts.


So we looked up a new rebuild and everything with 63 amps shows them with built in regulators. I am almost for sure, back in the day most all regulators were on the firewalls.


So I went home and checked the build sheet I have for this car and it says I should have a (EB Alt.& pulley). The car has Power drivers seat, windows, door locks, AC, cruise, but no rear window defogger. The chassis manual says I should have a 61 or 63 amp. But it does not tell me what a EB coded Alt. should be. I have a 350 engine not a 455.


When I disassembled the car I did remove a regulator from the fire wall. This car has been a growing mystery of "What did they do this time?" I want to put things back the way they are supposed too. The pictures are what I have now. I need some help figuring this out please.

rcorrigan5

Somewhere in the early 70s Olds went from voltage regulators on the firewall to having them internal to the alternator but I don't know when. Thru 68 they were on the firewall. In 69, the 4-4-2 models got them internal to the alternator while the Cutlass and F85 models kept them on the firewall. This is where it gets fuzzy. I seem to recall that, in model year 1970, everything went back on the firewall again before somewhere in the early 70s everything went to the alternator.

If you had a voltage regulator on the firewall but the newer style alternator with an internal voltage regulator, it's quite possible someone converted your car before you owned it. That's especially true if your assembly manual shows that you should have a firewall-mounted voltage regulator.

Randy C.

AJFink

I don't have a problem converting to internal regulators. I can dummy the firewall regulator to look factory OEM. But I do want to do this Right.

RocketDevo

The actual original stamped part number you need is 1100553. It is a 63 amp Alt. 1100571 or 1100591 are the same 63 amp and will also work. A 1971 Cutlass with a 350 is a externally regulated Alt. The 442's are the only models to get the internally regulated alternators. The "EB" code is a stencil stamp on the alt and is not useful in determining application, especially since it has long worn off. FYI 442's from 1968 to 1971 all had internally regulated alternators, the Cutlass line are externally regulated along with full size cars. In 1972 all vehicles were externally regulated including the 442. Most repair shops will automatically upgrade the amp output these days.

AJFink

So if the previous owner installed this alternator with the external regulator in the system could that explain why this Alternator failed? This one looks not that old.


How does one change a system from external regulator to internal correctly with a dummy regulator on the firewall? I don't mind it looking stock with something different with it better/more reliable.


When I went to NAPA today we could not find a Alternator with 63amps that has the same plug that this alternator has. The spades are opposite of these. If I give them the part numbers you list can they find an alternator? I'm just guessing as to how the parts system works.


Sorry so many questions

2blu442

Here's some threads on changing the alternator from the factory external to the newer internal regulators. If you can wait until you come down I've got a pile of core alternators you could pick through. John

https://classicoldsmobile.com/forums...onversion.html

https://classicoldsmobile.com/forums...-question.html

https://classicoldsmobile.com/forums...r-68-72-a.html

AJFink

Thanks John This will help a lot. I'll be sending you an email about when I'll will be coming down.

RocketDevo

An internally regulated alternator that has an external regulator will definitely cause a fail. The part numbers I listed are original Delco-Remy numbers, which unfortunately retailers and shops no longer go by. The spade type differentiate internal from external. The two parallel spades denote external. 2Blu442 will have a core that will work. It is easier to stick with the factory setup. You can buy kits to rebuild yourself or have a shop do it. They can make the output amperage whatever you want.

AJFink

Thanks RocketDevo
I'll be going down to meet 2Blu442 hopefully in a couple of weeks and we will be talking about this modification. The core I have is the one that came in the car and the plug is already in the harness. So at least I have a starting point. I'll be digging the harness out of storage to check how it was wired. I'm still along way from a running car but want to try and address these problems as they come up.
This forum has been so helpful!! It will make this restoration a lot easier to complete having all this knowledge available.