Scotty B

After my 72 442 Vert with a 455 had to be jump started 3 times, I suspected an electrical problem, and confirmed it with dying electrical systems on the way back home, culminating in the car just dying in the street. Fun...
The battery checked good at the parts store, over 12 volts and 756 amps from an 800 amp battery. So I installed a new alternator, hooked up my freshly charged battery, and the car cranked right up. Within 20 seconds, the alternator screamed, poured out smoke and I set a speed record for diving for the ignition to turn it off. What gives???
I have disconnected the battery and am stumped.

stellar

Screamed? Explain please. Maybe the belt is loose. Any spark at the battery when connecting or disconnecting? So far it sounds like a loose belt or defective alternator. More info please. What type of alternator are you using? Any problems before? Has the car been in use on a regular basis?

Scotty B

The alternator made a loud squealing noise and started smoking. Standard GM remanufacture alternator from O'Reillys. No sparks from the battery terminals. I did hear a heavy "click" when I attached the hot terminal to the post.

stellar

Scotty, If the alt made noisr like a squeel, it is bad or the belt is loose. A loose belt with a load on the alt will make it squeel and smoke. Check belt tension 1st.

MDchanic

Yeah, if the belt is loose it will squeal and, if allowed to continue slipping against the pulleys, will smoke.

The alternator turns freely, right?

How tight did you make the belts?

- Eric

Lady72nRob71

Stock setup or external reg?
That seemed pretty catastrophic. I would take the alt back to the store and let them test it. I have heard of others having issues with reman units right out of the boxes.

stellar

Does your alternator lite work? Did it come on when you needed 3 jumps?

Olds64

I agree that you should take the alternator back to the store and have it tested. If it is bad just swap it for another one. I've never had any problem with rebuilt alternators before. That is definitely a catastrophic failure.

Scotty B

All, thanks. The Gen light is either burned out or not connected (bummer) so its no help. I Sharpie-marked the position of the belt tension bolt on the brace, and crow-barred it back to the Sharpie mark. Same procedure I did when I replaced the fuel pump last month. The belt tension felt the same as before I removed the old alternator. I'm not much of a mechanic, but I'm willing to learn! I just want my 442 to be as fire safe as it can be. I had the car re-wired from front to rear bumper while in storage, so maybe there is a short somewhere, or maybe a bad volt reg???

MDchanic

So how tight IS the belt?

And DOES the alternator spin freely?

- Eric

Scotty B

Well, upon further exam, I may have identified a problem...with the alternator installed, should the gold fan spin freely, and wobble front to back? And should the nut on the front (towards front bumper) have daylight between it and the lock washer? And I can spin that nut by hand...I think this alternator was not QC'd properly at the factory when they assembled it.

stellar

That is scary. That is why I prefer home grown products. Replace that alt ASAP. Put the sharpie back in the pocket protector and make sure the belt is tight. Not all pulleys are the same size.

oldcutlass

As stated above, return and exchange it. Then tighten it until it's tight not to the mark you made. Also if you have an external regulator mounted on your firewall, get it checked also.

Scotty B

Man, I thought the Sharpie was a great idea! OK, so do I measure "Tight?" The belt has no slack or play, and feels like it did before the swap. I used a crowbar and put some elbow grease into it. Can you torque measure belt tension? How do you measure tightness (on a belt, that is)

Lady72nRob71

Wow - a crowbar? I pull the thing with my hand as tight as I can get and it is fine. Not gorilla tight nor sloppy. No issues...

Scotty B

Eh, it's a short crowbar...

oldcutlass

I use a long screwdriver, should be around a 1/4 inch deflection in the middle of the belt run.

BILL DEMMER

gotta love those remanned alternators....

i use a belt tension gauge, probably a museum tool these days. the belt usually ends up with about a 1/2" of up and down flex, midway between the w.p. and alt. pulleys, with my thumb and forefinger deflecting the belt. another method that i've used is the "slip test". turn the alternator fan with your thumb and forefinger, it should be fairly difficult to turn the fan against the friction of the belt, but not impossible-impossible is too tight. in any event, if the belts squeals under heavy alternator load, especially with a snapped-open throttle from idle, the belt is loose.


bill

stellar

Lets get the alternator lite working. Are you running an alternator with an internal regulator or one with an external regulator?

Scotty B

I think it's an external regulator; would not know it if it bit me. No clue how to get the Gen light working again. It and the Brake light do not illuminate in ACC, on, or any condition. Can I pull the gauges out without pulling apart the dash?

oldcutlass

The only way the brake light will illuminate is if the E-brake is pushed down. The voltage regulator is just inboard of the master cylinder. Disconnect the plug and unscrew it from the firewall. Then take it with to the auto parts store and have them test it when you get your alternator exchanged.

Scotty B

So the OLD alt tested bad for a bad volt reg (internal). The NEW bad alt was returned and refunded. A NEW-NEW alt is on order...Wed I hope.

MDchanic

So are you sure whether this car has its original external regulator or has been changed to an internal regulator?

- Eric

Lady72nRob71

Didnt a variant of the 72 442 get an internal reg?

BILL DEMMER

iirc, olds stopped having internally regulated(10si) alternators as standard on the 442, in '72, and switched to having the 10si as standard on the toro. maybe the 10si was available as an option? someone will correct me if my memory is hazy.


bill

z11375ss

Here's one for you. When I was 16 I worked at a place that remanned GM alternators and starters. After assembling an alternator we put it on a flow bench to see what it would put out. If it passed it went into the box and off it went. So, one day we get an order for 70 alternators that has to be filled pronto. I get to building these things and get a bunch done. I put one on the test bench and the super looks at me and says WTF are you doing? I told him I was testing it. He said, "Get 'em built, get 'em boxed, don't test them. We don't have time!" That really opened my eyes as to what kind of crap companies could put out. Needless to say I told all my friends not to use the products from this business that were being sold in our area. Lesson? It may be that the Alt you put on is junk!

nsnarsk65cutlass

Back in about 91-92 i did a tour in a starter alternator rebuilding outfit,they tested em and liked seasoned parts over new ones.I didn't like it at the time but the aftermarket is just that.ie china crap for the most part.

stellar

Scotty, don't pull anything apart until you make some tests. Wait until you get the new alt and we can go from there. One step at a time. If you can take some pictures it will help. My application guide shows a 1972 with a 455 as having an internal reg alt. I suspect this is what you have, but I do know 72 olds used both internal and external regs.

Scotty B

OK, should have the new internal reg Alternator on Wed. Not sure what came with it originally.

Scotty B

SUMMARY: Car died, battery checked good, first re-man Alt was bad (not assembled correctly)...new re-man 63 amp Alt and ext VR went on today...Smokin!

I replaced the alternator and external voltage regulator today, got everything hooked up, started the car, and no problems for 30 seconds. Then...smoke starts curling up from the voltage reg on the firewall. There was a question about whether a 61 or 63 Amp VR was required, but since the Alt was a 63 amp, I bought what I THINK is a 63 Amp VR; it might be a 61 Amp. When you cross-ID NAPA to AC DELCO, the parts "match" but the description didn't specify clearly 61 or 63 amps.
If it was a 61 amp VR, would it smoke after 30 seconds with a 63 amp altenator, or do I have a bigger issue on my hands? The parts-shop guy thought if it was a 61 amp, it would not last as long as a 63 amp, but probably work ok.

MDchanic

For the love of Pete, do you have an internal or external regulator, whichever it is, was it original to the car or changed later, and if changed, who did the wiring, and how do you know it is good?

Have you tested out all of your charging system wiring to make sure that everything is connected the way it's supposed to be?




I've never heard of 61 amp or 63 amp regulators - perhaps Stellar can shed some light on this.
I always thought they were the same thing.

- Eric

Scotty B

I was three when the car was made, so I'm a little unsure what it came with originally or for the next 37 years. I've owned it for 5 years, the last 4 it was in storage while I was overseas. I did have the whole car rewired in 2011/12 by a guy in Bismarck, ND.
Whatever it came with originally, it has an external VR on the firewall with a bunch of wires on it. I compared an internal vs an external Alternator today; my car needs an external Alt judging by the plug prongs and the wire plug on my car's Alt set up. I visited 4 parts stores today, and nobody could tell me what type or Amp external VR to buy. Most everyone thought 61 Amp (code VR 103)but several AC Delco and Olds part books call for the 63 amp (code VR 171). I'm confused, but I know my car don't run.

MDchanic

So somebody you didn't know rewired your entire car while you were on another continent.

Danger, Will Robinson.

Sorry, but phantom car-rewire-ers are guilty until proven innocent.
Did the car run and charge after it was rewired?



Thank you.



This is not a confidence-inspiring turn of phrase. A picture of this "bunch" may be helpful.



So the plug goes into the back, and the prongs look like this: ( | | ).
The plug does NOT go into the side, with prongs that look like this: (— —), right?



Far as I know, the VR-103 is the standard, used-in-everything GM regulator for everything but high-output alternators of that era.

- Eric

stellar

If the regulator was a new mechanical style regulator it is normal for them to smoke the first time used. There are resistors on the underside that have a coating and it will burn off in a short period of time. vr103 and vr171 are not delco numbers, but I think they are for a company called Standard. I think the 103 is for 37 amp and 171 is for 61 or 63 amp. There should be no difference of a regulator for 61 amp and a 63 amp. See if the reg you bought crosses to a delco # D663 or 1119515. I would start it again and see if the smoke stops after a few minutes. You need to start testing the output. Do you have any meters to test with?

oldcutlass

This diagram shows what the wiring would look like if it were converted to an internal regulated alternator.

If it was not converted then the wiring would go to the voltage regulator.

new_alternator_wiring_pic2.jpg

With the engine running, if he disconnects the battery and it stays running everything should be operating correctly.

stellar

It is probably not a good idea to disconnect a battery while the car is running. It probably would not cause damage if this car is all original, but on anything later than 72 or a car with electronics in it should not be run without the battery resistance in the circuit.

oldcutlass

It will tell him if his alternator and voltage regulator is functioning, and will not damage anything. I've tested older cars this way for 40 years and never hurt one.

I had a battery explode out in the boonies when it went dead on a friends car back in the 70's. We jumped it off and drove 30 miles without a battery in the car at night with the lights on because...well, it was at night and we were in the boonies.

BILL DEMMER

disconnecting the battery on a running vehicle is a good way to fry an alternator.


bill

oldcutlass

Bill, I assure you it won't.

BILL DEMMER

delco remy disagrees with you, and i do too. to each their own...


bill