Chad Were Wolfe

My brother has a 91 Camaro with the V6 engine and I've replaced the alternator for the third time now and I'm beginning to wonder if there's another issue causing these failures or if I'm just really unlucky with these Duralast rebuilds. With this latest one the voltage meter is reading at about halfway between 13 and 18. Is that right for this car? I'm more of a Jeep guy and don't have as much experience with Camaros so any help is greatly appreciated. Thanks in advance!

jkris53406

iTrader: (5)

Use a voltmeter to check the actual voltage at the back of the alternator and at the battery. Have you had the alternator checked off the car? Also, a battery with a bad cell can cause bad readings.

SilverChicken

iTrader: (1)

Do check the alt's output and most parts stores can check the battery for a dead cell. Also, its very likely your just getting junky rebuilds. I went through 4 power steering pumps before finally getting one that lasted for my pickup. The reman steering rack on it leaks worse than the factory one it replaced.

Vader

What is failing on the alternators? Is is a mechanical failure (bearings or brushes)? Is it a rectifier or stator failure (from overload)? Is it a regulator failure (from wiring or connection problems)? That will help indicate where to look on the vehicle.

As for the charging voltage, after the battery has been recharged upon starting and everything is at normal operating temperature, the system voltage is usually 14.5 volts ±1V. This should be measured at the alternator output stud with a real meter. That thing in the instrument cluster called a "voltmeter" is merely an indication, not a true instrument.

Tibo

iTrader: (15)

The way the factory has it wired is undoubtedly wrong. It just ties in with/from the switched power for the gauges. Could be a true gauge if you placed the gauge's sense wire on the same location as the alternator sense wire or one of the power distribution studs.

Reid Fleming

iTrader: (2)

I went through 3 alternators and 3 batteries in 3 years. (Daily driving) These were Powermaster 140 amp and stock 105 amp alternators. Batteries were all your standard 650 CCA batteries. I figured it might be the heat from the engine (I'd just moved from Canada to the southern US). High ambient heat and humidity plus non stop A/C use. But it still didn't make sense. Every other car in the city doesn't have this problem.

I finally replaced the battery cables with a set of custom made, large, thick, cables from Innovative Wiring. Problem solved. The original battery cables looked fine. No corrosion on the terminals. Outer black wrap was clean. No tears etc. But I suspect the inner cores of them had corroded to the point of building up high resistance. When that happens, your alternator runs flat out trying to charge the battery. While the battery gets reduced charging output. Both end up dying quickly.

I'd also recommend getting one of those digital volt gauges that plugs into the cigarette lighter. If you're getting less than 10 volts during startup, your battery is on it's last legs. If you're seeing it run higher than 14.5 volts with the car on, your alternator's regulator isn't working right.

In the winter weather, it will spike right up to 14.5 and gradually draw down to about 13.5-13.8 as the engine warms up and the battery reaches full charge....During warmer weather it tends to run about 0.5 volts less across the scale.

I've also noticed that the cigarette lighter volt meter reads 0.2 less than what my volt meter reads when applying it to the battery terminals. So if I'm seeing 13.4 in the car, I would be reading 13.6 when measuring the battery myself.

Reid Fleming

iTrader: (2)

After the success on the GTA with the battery cables, I bought another set for our Blazer. Here are some comparison pics between stock Blazer vs Innovative Wiring.





Starts better, headlights are brighter. Turn signals are quicker. No down side really.

Tibo

iTrader: (15)

The cigarette lighter volt meter and the dash gauge volt meter would be, for all intensive purposes, reading from the same location. If there is a descrepancy then one of them is more accurate. Voltage can vary based on where you are measuring it from. Ideally you want the alternator to feed one distribution point and have all the power radiating from that point. The system that our cars use has too many distribution points and feed lines and coupled with a poor grounding system makes it so voltage varies all over the car. It's entirely possible to have a perfectly functioning stock system with one voltage reading at the battery, one at the alternator and one at the fuse block and one at a switched power wire.

Chad Were Wolfe

I had it checked at the auto parts store with their vehicle diagnostics tool. It indicated that everything is fine except that the battery was only at half its rated amperage. Which means it was drained by the last dying alternator. Fun stuff.

I think that's the case too but I wanted to confirm my thoughts here. Is it just me or do parts from these auto parts stores just seem to be going down in quality? I've had so many issues in the past 5 years with cheap parts.

They stop putting out current as far as I can guess and the car runs off pure battery power until the battery dies. When they test the dead ones at the auto parts store they never told me what failed and I didn't think to ask unfortunately.

I had the vehicle tested at an auto parts store with one of their on-board vehicle testers and if that's something to trust then everything is fine with this latest alternator at the moment except for the battery being about half dead from the last failing alternator. I may have to check the voltages myself at some point to see if everything checks out. Thanks for the tips!

Well that's interesting. Thanks for the info!

Better battery cables seems like a good upgrade to try and I'll have to check out one of those volt gauges. Thanks for the tips!

Do you happen to have a link or part number for one of those for a camaro?

Chad Were Wolfe

Thanks again to everyone for the replies and helpful insight!

redneckjoe

i had a similar issue as Reid pointed out with old, bad wires. seems like i put a new/rebuilt alternator on there every year? i finally added a second 10 gauge wire from the alternator stud back to the battery and problem solved.

paulo57509

I used to see this on occasion in my Dad's shop. Slicing and peeling back the insulation, you'd see a bunch of green fuzz down the length of an otherwise perfectly good looking cable.

Chad Were Wolfe

I could do that maybe for now. Is that to the positive terminal or negative one? Thanks!

I'll definitely be looking into replacing them. Thanks

Chad Were Wolfe

And a little update for anyone interested. At some point the radiator fan motor died and I replaced it today. Not sure if that bad motor could cause additional stress on the system. And while putting the negative battery cable back on I noticed the threads are just about gone which could also be part of the problem maybe? So I'll be replacing the battery cables as soon as I can for sure.

Tibo

iTrader: (15)

Replace and upgrade the cables. Be sure that either the ground and positive wires are the same size or there are several good size ground wires for your one thick power cable. I would run at least a 4 gauge power cable and three 6 gauge ground cables. One ground to the block, one to the inner frame rail that the K member bolts to and one to the core support. The factory runs a ground wire to the top outer frame rail that the fender bolts to but I think the rail i suggested is better to use since it ties into the firewall and floor pan.

Chad Were Wolfe

Yeah. I think I'm going to upgrade the wires in the near future with some of those Innovative wires that were mentioned previously. I just have to figure out which ones I need first. Thanks for the info!

redneckjoe

i added 10-gauge wire from the main stud on back of alternator to the battery positive terminal.

86CamaroDan

I know im a bit late to the party but....

Theres your issue. When i switched from a 86 belt setup to a 88+, i bought a AZ alternator because it was cheap and i figured even if it crapped out, it was easy to replace. Plus how do you screw up a alternator? Well, i went through 3 alternators until i finally threw the last one in the trash and put a GM one on it. Never had a issue since.

Chad Were Wolfe

Thanks!

Better late than never! Yeah, I think I'll avoid them from now on, lifetime warranty or not. Thanks!

Lucid

iTrader: (4)

On my 86 camaro I had the SI alternator design, I think it was 108 amps and a Duralast reman unit. I would replace that thing just about every 8 months or so. I would see the lights start to dim at night and pop it out, and the bridge rectifier was black. I warrantied it out so many times that the manager said no more and refunded my money. I then bought a brand new Duralast gold CS144 140amp from them and swapped that in. Haven't had problems since.

Matter of fact, I read about it on this forum and bought a used one from a junkyard 95 caprice and that unit went in that car until I bought the Gold and it's now still alive in my 87. I got it 13-14 years ago. I think those V6's came with a CS130 or a CS130D and they kind of suck. I had one in my 87 and when it died, I was happy to trash it.

I have heard of people swapping in a CS144 for the CS130 but I'm not sure what's involved. You would need to measure the bolt spacing to see if it would fit your current bracket setup. I have this alternator in my 2 camaros, my dads camaro and his pickup truck. I would recommend getting a new alternator and not a rebuild at one of the parts store. I usually tend to go with O'reilly auto parts for the electrical stuff. If I am low on funds, I will try to find a good deal on a new Delco unit on Rockauto or Ebay.

Also, I'm not sure what you said is stripped thread wise... but you do know you can pop the side terminals out of the battery cables and replace them right? They are like $2.50 or something at Walmart. They are kind of a pain to get in and out of the little rubber piece, but they will go in. I usually use the ratcheting battery wrench to remove them from the battery, and then turn the wrench around and use the handle to push the terminals in and out.