[67Dan]

George,

On the regulator, I know number three is full voltage! What should the other locations show? F 2 and 4?

[Old Goat 67]

Dan,
Did you read AC Voltage on the battery connection on the alternator?

[GT182]

Do like I did Dan.... go to an alternator with the internal regulator. You can keep your wires hooked to the regulator on the firewall, but you'll have to jumper the male tabs back under the cover so the harness will still plug to it. Solder a piece of wire across 1&3and 2&4. [I think that's it.] Gut the regulator and your problem(S) should be cured. It'll look original only if you keep looker's noses away from the new alternator.

[67Dan]

Drum roll please!

After dicking with the problem for so long and worrying it could be something else causing the insane embarrassing buzzing and it was VERY LOUD at 700RPM. One guy told me to just unconnect the regulator when it does it and see what happens! I got under the hood and revved the engine to 700 and boy did it buzz. Disconnected the regulator and it was quiet and I even used my Wife’s stethoscope! I noticed there was always vibration all the time!

Well, after weeks of checking and nothing but pure aggravation went to NAPA for an alternator. All they had were the Delco internal regulated ones, and I was tempted…oh so tempted, but a bit stubborn and all the cars I had when I was a kid had external ones!

NAPA had to check, but found one in back. I came home started unbolting everything, put it on and Charles called and I told him I would call him back, because it was getting dark! Got everything on and rechecked to make sure I had tightened everything!

Also a plug for the flex head box end ratcheting wrenches, whoever invented them, must have had a GTO. I hope he is wealthy and living on an island, because they are so handy!

To shorten the story, cranked her up and cold she was running about 1,100. Waited till she warmed up and stepped on the gas to idle her down. She goes to 600, but remember 700 is the magic number! I eased her up while looking at the tach and for a second I thought I heard something and then quiet! Nothing! Went outside and eased the RPM’s up with my hand and felt the Delco regulator……QUIET! I noticed I was always feeling a vibration, but at 700 Rpm’s she went berserk! Just sheer joy!

I would like to thank all those that put up with all the questions from me! George I very much appreciate your council and all the help! This was a bear for me and I’m not an electronics major! Also Charles you have been there with me from the beginning of this journey with my car!

I just love my GTO!

Now to work on the water pump problem! One down!!

[GT182]

We knew it had to be a bad alternator. Gut feeling.

See, now yer getting a proper education Dan... it ain't a Chevy. LOL Welcome to the wonderful world of Pontiacs.

[67Dan]

Wish you would have said that two or three weeks ago!(LOL)

[Old Goat 67]

Hooray, thanks for the help George.

[GT182]

I did Dan but yer too far a way and couldn't hear me. LOL

[67Dan]

Well, I thought I had the problem licked and it is buzzing again, but not as bad! I'm wondering if all the strain on the regulator damaged it before I got the new alternator? It is not as bad, but the magic 700 RPM still exists. Goes away below or above!

[GT182]

Which alternator are you running as of right now..... internal regulator in the alternator or on the firewall?

I think I'm reading right and it's the stock alternator for 67. Right?

[67Dan]

NAPA 123-4013. The base external regulator that is 55 amps. It is made by Delco and is a reman, but seems fine! Want to keep the car original with the external alternator.

I put the other regulator back on from Standard and for now it runs fine and no buzz at 700, but it's too soon to tell! Might have messed the Delco regulator up! If this doesn't work then I'll go to the internal regulated, but will have to find a link with instructions and picture to shw me how! From what I heard not a big problem!

[Old Goat 67]

Dan,

Is the Battery bulb in the dash in there properly? That bulb should light with key on and engine not running.

If it's not, maybe it could have something to do with that relay fluttering? I know it has a part in the circuit, but not sure just how much an importance it plays.


Charles

[67Dan]

It doesn't come on when the key comes on! Remember there are so many wires I found not hooked up. Wish you could circle the circuit where I should look and give me an idea of where or what I'm looking for! Remember Peter mentioned that some time ago. Odd it would be hooked into the same circuit!

It didn't buzz with the change to the older Standard regulator, but I haven't driven it much yet!

[Old Goat 67]

Dan,
Look in the Shop manual, page 6E-18. It shows the lamp in the circuit and it is the Battery light in the dash. Top lamp left pod, see below. Red & Pink leads on bulb socket.

Charles

[67Dan]

How hard is it to get to???? Remember I had the Vintage Air Gen IV system put in and I hate working under the dash! Is it accesable?

So you think the wire is not on or the bulb is out? I need to get the other ground wires on the car as well! Just havn;t got around it with the other problems.

The Standard is not buzzing. I'm wondering if the bad alternator caused some problems with the unit. I'll talk to Jimmy ans see if he can swap out the Delco!

If it doesn't rain tomorrow, I will look under the dash. But my main focus is the water pump.

[GT182]

No Dan it's fairly easy to do. What I said above for the jumpers on the firewall regulator are wrong. My bad.

Here's the photo showing the jumpers on the correct tabs. #1(bottom) goes to #4(top) and #2 to #3.

I believe instructions are included to wire the alternator and a plug comes with it to hook into the old wiring. Red to black/white wire and solid white wire to green wire. I thought I had gutted the regulator but wrong again. I did cut the wires from the guts to all 4 tabs on it so no juice goes thru the regulator. Make sure you use an old regulator and NOT your new one that works. To connect the wires together I used male and female connectors, just in case the plug for the alternator has to be change.

Sorry but I can't seem to get a good clear photo of the alternator's wires.

[67Dan]

Thanks for the photos of how you switched to an internal regulated alternator!!

Charles, I noticed the wires in the schematics show the ammeter wire going to number 4 post on the regulator and that goes to an internal switch! Damn odd to me. Now you are telling me if the bulb was burned out it would make a buzz or the wire not hooked up?? Surely Pontiac was not that stupid?

[Old Goat 67]

Not just Pontiac Dan. They were all the same.

[67Dan]

Still GM!

Now you’re telling me if the lamp goes out, the wire is unplugged, you were going to get a buzzing like I did, although mine occurs pretty religiously around 700RPM! Then vanishes!

I do think the buzz was there all the time from me holding the regulator at different RPM’s, but it seemed to peak or really get bad at 700! You heard the sound on the video on how bad it got! When I changed the alternator out I thought I had it solved and then it came back, but not as bad! I put the Standard back on this morning and with only one test seemed fine!

Wanted to drive the car to the Grandkids birthday party, but they were talking about rain so did not! May tomorrow before I start on my next challenge the water pump!

You must live on this site!

[Flatfish]

I had the same problem with a LOUD buzzing from the regulator on my 64 at low rpm's. I pulled the remanufactured alternator off and had my old 35 amp alternator rebuilt and refinished. And found my original regulator in the old parts box, switched covers and installed it, too. Problem cured. When I took the reman alternator in so the shop could take off the pulley and fan to go on the alternator being restored, the shop said the alternator had problems too, so I left it in their junk bin. So I know the alternator was bad, but also replaced the regulator while i was at it, just in case the bad alternator had damaged the regulator.
Cost about $125 to restore and refinish the alternator. A big plus is that the restored alternator looks much better in the engine compartment.