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Yesterday, I once again became the victim of a dead battery. A few months ago when this happened, I found that the map light on my rear view mirror had been left on so I didn't look any further. That was not the case here. This is the 3rd dead battery in the past 2 years for me. I decided to take the battery and alternator back to Autozone for testing. The battery which was only 3 months old was completely dead, so they gave me a new one. The alternator passed it's test too, but i found out something interesting.
The alternator that they sold me 2 years ago was not what I had asked for. This one was a 55 amp instead of the 63 that I had asked for and assumed that they gave me. They apologized, took the return and I should be getting the new 63 amp tomorrow.
The electronics has always been a weaker spot for me when it comes to expertise. Would running a 55amp instead of a 63 cause my battery issues? Or should I start looking further up the chain, like maybe the voltage regulator?
The 55 amp vs the 63 did not cause the dead battery unless you have very high load electrical accessories and the car is driven on a ton of short trips. Does the car sit for extended periods?
Get the car back together and then measure the voltage output at the battery on a slightly raised idle and post the VDC reading. we will figure it out.
Last edited by Sugar Bear; August 19th, 2024 at 06:03 PM.
Chip,
Model year and engine size.
Do you have a volt ohm meter?
Do you have a voltage regulator on the fire wall?
1971 Cutlass Supreme convertible, 350 4bbl
Except for the radio, I have kept her as stock as humanly possible,
No, I don't have an ohm meter yet.
Voltage regulator is on the firewall.
The 55 amp vs the 63 did not cause the dead battery unless you have very high load electrical accessories and the car is driven on a ton of short trips. Does the car sit for extended periods?
Get the car back together and then measure the voltage output at the battery on a slightly raised idle and post the VDC reading. we will figure it out.
Would raising/lowering the top count as "High load"? Other than an after market stereo, everything else is stock.
A little more info for context. I have noticed the last few times starting her up that she'd crank and crank for longer than normal before actually starting. Also yesterday, after about a 2 hour drive with a short break for dinner at a local diner, We got home and shut her off before realizing that I forgot to put the top back up. When I went to turn her over...nothing. Not even a click or a death rattle. No interior light or door buzzer either. My wife and I had to manually put the top back up.
That was a lot tougher than I was expecting.
Last edited by chip-powell; August 19th, 2024 at 07:43 PM.
Actually found an old volt ohm meter out in the toolbox that must be at least 25 years old. Not digital. Completely analog with a needle for showing output. Now I just have to teach myself how to use the d@mn thing all over again. I have'nt had to use it since I bought it and used it the one time.
Last edited by chip-powell; August 19th, 2024 at 08:01 PM.
Yes the top is higher load but it is for a short period of time, it isn't the problem. Does the aftermarket stereo have large powerful amplifiers or is it an in the dash stand-alone unit?
Prove that the old meter is good on a known good charging system before relying on it for testing.
On that trip home we're the lights on? Were they dim?
Charge the battery via a wall charger so you know it's good. Lots of time. Get down below 1 amp charge. You can check voltage across the poles while it's charging. Should be something like 14.7 VDC. Use that multimeter once you've read the instructions. Short version, set to DCV 50 and put red on pos and black on neg. You should see something greater than 12.7 VDC.
Shut the wall charger off, get it removed. Put the leads on the battery again. You'll see it slowly dropping to non-excited. It will stabilize at 12.7 or so. This is a charged, happy, but not BEING charged, battery.
Start the car. It will start fine. Put the leads on the battery again. You should see 14ish volts. Not 12.7. If you see 14ish volts, the alternator and voltage regulator are working. If you only see the battery voltage, they are not.
If you see 14 and some volts with the alternator running, put a load on it. Turn on the blower high (no AC) and the high beams. Check the voltage. Still should be 13 and some.
However, my money is pointing to a bad voltage regulator. Does the GEN light turn on dimly when you turn the ignition on and then go away once started, or does it never light? A bad voltage regulator is a bright GEN light. You would've seen it. I bet you have bad regulator and bad bulb. Fortunately, this is two connections and three bolts to fix. Disconnect battery on both ends to be safe while doing it, and to also check connections.
Gonna be a little longer until I can test everything. The alternator that was sent failed it's test, so I'm waiting on another. Between work and me needing to re-shingle my shed this weekend, it might be Sunday before I can get to it. I will keep you all informed.
I've always ballpark battery vs alternator by starting the car and disconnecting the battery while it was running. It if keeps running the alternator/generator was good and the battery was the the problem. Not quite 100% scientific but when on the road without the right tools it helped point to the solution.
When I worked at auto parts stores in the 80s we would test alternators before letting customers leave the store. It was amazing how many failed right out of the box.
I may sound like a broken record....Grounds grounds grounds!
Clean both ends of both the battery cables. Do both cables pass the resistance & visual test?
Clean all the other grounds you can get your hands on. All of the wire harnesses in your car have at least one ground.
The voltage regulator (VR) seeks its ground through the firewall. The engine is grounded to the firewall with braided cable to the heads. The alt and starter are grounded through the neg battery cable
Check the VR connector and the Alternator connectors etc...
The entire electrical system has to work harder with bad ground connections. Think of it as a garden hose. If you kink the hose the water will flow slower. Same goes for electricity with shitty grounds. The easier the path to ground the better the voltage flows. Bad grounds will take out many electrical subcomponents because they have to work harder thus get hot and break(down).
With the car reassembled the VR and alternator should out put ~14 VDC + .5 - .0. Usually like to see 14.3 to 14.5.
Once you have the car reassembled I can walk you through the VR and Alt test if you'd like.
I also recommend finding a good starter alternator generator rebuild shop.
I have one where I live that goes as far as using USA made components when they rebuild my sub-components. A house of china junk part stores is a sever crap shoot.
When I worked at auto parts stores in the 80s we would test alternators before letting customers leave the store. It was amazing how many failed right out of the box.
There are 4 AutoZone's within 10 miles of my house. The alternator testers were broken at 3 of them. When I was speaking to the manager at the 4th, he said that the testers at the other 3 probably aren't "broke". They were most likely too lazy to upgrade and re-calibrate them.
I can vouch that the quality of the people at allot of these shops have gone down over the years. A few years ago I went to one for one my daily driver. Nothing special, just a 2016 Hyundai. Don't laugh...I'm getting 40 mpg with it. Anyway, the battery was 5 years old and had finally given up the ghost. They offered a free replacement with the purchase of a new one. The kid working there had no idea how to change a battery. I was in no hurry and didn't have anything else going that day, so I stayed for a while and showed him how. Midway through, another kid came out and asked me to show him too.
Shouldn't this be part of the interview process for new hires? You would think that if you are going to work at an auto parts store, you should at least have an idea on what to do.
There are 4 AutoZone's within 10 miles of my house. The alternator testers were broken at 3 of them. When I was speaking to the manager at the 4th, he said that the testers at the other 3 probably aren't "broke". They were most likely too lazy to upgrade and re-calibrate them.
I can vouch that the quality of the people at allot of these shops have gone down over the years. A few years ago I went to one for one my daily driver. Nothing special, just a 2016 Hyundai. Don't laugh...I'm getting 40 mpg with it. Anyway, the battery was 5 years old and had finally given up the ghost. They offered a free replacement with the purchase of a new one. The kid working there had no idea how to change a battery. I was in no hurry and didn't have anything else going that day, so I stayed for a while and showed him how. Midway through, another kid came out and asked me to show him too.
Shouldn't this be part of the interview process for new hires? You would think that if you are going to work at an auto parts store, you should at least have an idea on what to do.
The scenario you related is extremely common. Autozone, Advanced Auto, Carquest, etc., etc. are likened to a Dollar General, Family Dollar store. Most have inexperienced, warm bodies w/ no training who have no stake in the game in this industry other than showing up for work, talking on their cell phone all day never supplying adequate/complete or correct information. If you want a true hardware store you go to a Tru-Value hardware store which has been in business forever & sells quality parts - or, take your chance with the Dollar Generals of the world which includes the big box stores. I've found in nearly all cases the best automotive parts store is a NAPA store. Your mileage may very based upon location, but NAPA (IMO) provides the best case scenario for knowledge & dedication to customer satisfaction. I'm on a soap box here, but I'll bet I'm not alone. Rant complete, I'll step down and see my way out.
The scenario you related is extremely common. Autozone, Advanced Auto, Carquest, etc., etc. are likened to a Dollar General, Family Dollar store. Most have inexperienced, warm bodies w/ no training who have no stake in the game in this industry other than showing up for work, talking on their cell phone all day never supplying adequate/complete or correct information. If you want a true hardware store you go to a Tru-Value hardware store which has been in business forever & sells quality parts - or, take your chance with the Dollar Generals of the world which includes the big box stores. I've found in nearly all cases the best automotive parts store is a NAPA store. Your mileage may very based upon location, but NAPA (IMO) provides the best case scenario for knowledge & dedication to customer satisfaction. I'm on a soap box here, but I'll bet I'm not alone. Rant complete, I'll step down and see my way out.
Been to the NAPA store in my town a few times. The quality of the guys working there is no better than the other stores. Although usually the quality of the parts is better, if more expensive. The main reason for me to go to Autozone for certain parts is the length of their warranty. If one of their parts goes bad, even after a few years, I can usually just walk in with it and they give me a new one for no charge.
I may sound like a broken record....Grounds grounds grounds!
Exactly. Greater than 90% of all electrical issues reside on the negative (-) ground side.
OP should perform/ensure all steps outlined for cleaning all ground terminals/posts have SOLID metal-to-metal connections.
Alternate example/analogy.
Batteries have massive electron potential chopping at the bit to move from the negative (-) ground battery post to the enormous amounts of electrons contained in the metal on the block, frame, chassis, etc. Electron flow is how the entire electrical system operates to provide power to all devices. Poor ground connections found anywhere can (often do) create significant increases in resistance to electron flow. This resistance reduces/diminishes electron flow making it: (1) difficult for devices to complete the electrical circuit (and return to the battery positive (+) power post [likely candidate in your scenario]); (2) can create significant heat w/in any electrical circuit (heat kills); (3) causes premature wear on devices; and, (4) oft times difficult to reveal, but a significant increase in electrical resistance (impedance) can cause a battery to go belly up even when a ALT is supplying a good duty cycle to recharge the battery. That battery can go South in a heartbeat if the ALT is continually recharging a battery which is continually being met with increased resistance to electron flow via failure of solid metal-to-metal ground connections - battery plates begin to disintegrate, battery cannot maintain charge & continually is discharging, battery sulfation (build-up of sulfate crystals is number one reason for early battery failures).
I'll chime in, as well - grounds, grounds, grounds.
Last edited by Vintage Chief; August 21st, 2024 at 08:11 AM.
The main reason for me to go to Autozone for certain parts is the length of their warranty. If one of their parts goes bad, even after a few years, I can usually just walk in with it and they give me a new one for no charge.
That reminded me of my neighbor changing his starter for the 4th time. He said it was good AutoZone gave a warranty, he just was pissed he had to use it so often. He said buy elsewhere as he couldn't recommend AutoZone. Having worked at a couple of "real" auto parts stores in my youth (local family owned) , I completely agreed with him.
Exactly. Greater than 90% of all electrical issues reside on the negative (-) ground side.
OP should perform/ensure all steps outlined for cleaning all ground terminals/posts have SOLID metal-to-metal connections.
Alternate example/analogy.
Batteries have massive electron potential chopping at the bit to move from the negative (-) ground battery post to the enormous amounts of electrons contained in the metal on the block, frame, chassis, etc. Electron flow is how the entire electrical system operates to provide power to all devices. Poor ground connections found anywhere can (often do) create significant increases in resistance to electron flow. This resistance reduces/diminishes electron flow making it: (1) difficult for devices to complete the electrical circuit (and return to the battery positive (+) power post [likely candidate in your scenario]); (2) can create significant heat w/in any electrical circuit (heat kills); (3) causes premature wear on devices; and, (4) oft times difficult to reveal, but a significant increase in electrical resistance (impedance) can cause a battery to go belly up even when a ALT is supplying a good duty cycle to recharge the battery. That battery can go South in a heartbeat if the ALT is continually recharging a battery which is continually being met with increased resistance to electron flow via failure of solid metal-to-metal ground connections - battery plates begin to disintegrate, battery cannot maintain charge & continually is discharging, battery sulfation (build-up of sulfate crystals is number one reason for early battery failures).
I'll chime in, as well - grounds, grounds, grounds.
Before I start conecting things up and testing with my new multi-meter. I'm attaching a few pics that are giving me questions. In the one, is a diagram that I found online (might or might not be correct). It shows in addition to the external plug wires that go back to the voltage regulator, a red positive going to a junction box, and then a black ground wire also. The next pic is me holding the only 2 connections that I currently have from my car to the alternator. One is obviously the plug, the other I had always assumed was the positive. I thought that the neg went back to the regulator through with the plug.
Correct or incorrect, this is the set up that my Olds has been running on for the past 11 years that I have had her. This is also the beauty of the internet. I'm now reading on the net that the ground wire for the alternator may not be completely necessary because the alternator is grounded through it's bracket connections to the block. Sounds like crap to me, but as I said in the begining of this thread, electronics is not my forte.
My wife just reminded me of a change made to the electronics. When I bought the replacement radio (200w no additional amps added), I could not get the power to work on it. I took it to a local car stereo guy who wired the radio power input directly to the battery.
Charge the battery via a wall charger so you know it's good. Lots of time. Get down below 1 amp charge. You can check voltage across the poles while it's charging. Should be something like 14.7 VDC. Use that multimeter once you've read the instructions. Short version, set to DCV 50 and put red on pos and black on neg. You should see something greater than 12.7 VDC.
Shut the wall charger off, get it removed. Put the leads on the battery again. You'll see it slowly dropping to non-excited. It will stabilize at 12.7 or so. This is a charged, happy, but not BEING charged, battery.
Start the car. It will start fine. Put the leads on the battery again. You should see 14ish volts. Not 12.7. If you see 14ish volts, the alternator and voltage regulator are working. If you only see the battery voltage, they are not.
If you see 14 and some volts with the alternator running, put a load on it. Turn on the blower high (no AC) and the high beams. Check the voltage. Still should be 13 and some.
However, my money is pointing to a bad voltage regulator. Does the GEN light turn on dimly when you turn the ignition on and then go away once started, or does it never light? A bad voltage regulator is a bright GEN light. You would've seen it. I bet you have bad regulator and bad bulb. Fortunately, this is two connections and three bolts to fix. Disconnect battery on both ends to be safe while doing it, and to also check connections.
Finally had a little free time this weekend. Here's what I found during the multimeter testing;
New battery before install 12.63
After starting 13.29
5 minutes after starting 14.25
with a load going (heater on high, headlights and interior lights on, radio on) 12.65
3 minutes after full load started 12.34
3 minutes after shutting lights, blower and radio off 13.20
I have a new voltage regulator. I just haven't had a spare minute to install it this weekend.
Chip an externally regulated Olds alternator has the blue and white wires going to the voltage regulator like you have. That is good. Figure out where those two red wires go. There should be one, and it should go to the pos power distribution point. The other one should be figured out.
Those voltages are a little low. Try the new regulator.
Chip an externally regulated Olds alternator has the blue and white wires going to the voltage regulator like you have. That is good. Figure out where those two red wires go. There should be one, and it should go to the pos power distribution point. The other one should be figured out.
Those voltages are a little low. Try the new regulator.
Had time to get under the hood today. The 1st thing that I noticed was that I had not seated the plug into the new alternator all the way. Took care of that and then hooked up the new voltage regulator. The battery at that point was reading 12.75.
Started her up and almost immediately noticed that something was wrong. The gen light came on and was steady. As soon as I tapped the gas to lower the idle, the gen light was no longer steady but kept flickering. I checked the battery, and it was doing a constant up and down rapid spike between 13 and 16.2.
Shut her down again and hooked up the old regulator. Here are the readings...
running no load 5 minutes 13.5-13.6
running full load (vents, headlights, interior lights and radio) 14.5
running full load w/ the a/c 12.38
I'm wondering if the plug seating in the alternator screwed up the readings from before. I did noticed one other thing. The 2 coils on the back of the old regulator are the same size. On the new one, the large one is the same as the old reg, but the 2nd coil is much smaller. I wonder if that made a difference. Attached is a pic of the back of the new one.
August 19th, 2024 | 05:31 PM
