4th Alternator in 2 months????

[3sacrwd]

I replaced my 4th rebuilt alternator bought from O'Reillys auto on Sunday. The other alt did test as bad, so I got yet another one. I installed it on Sunday, and I got 13.5 volts or so on the charging system. I go out on Tuesday to drive, and now I am getting 10.4 volts or less, and my dash goes out when I push on the brake pedal....I did not drive it, because I knew it would die on me.

This is my 4th alternator in 2 months, but only 15 or so miles....Is there any chance that I am burning them out, or otherwise damaging them?????

My idler pully looks to be at the far end of the hash marks, could my belt be too loose to turn it, and then burn it out. Everytime I took it back to the auto parts store, they would test it, and it would of course test bad.......

What the heck could it be?

Thanks for the help.ad ad

 

[wallyknoch]

Some electrical problems are tough! I was just wondering, how much did you pay for these alternators?

 

[3sacrwd]

I think I paid around $75 for the "lifetime" warrantied Ultima alternator....They have replaced under warranty the other alternators. My first one from them lasted about 12 months, after that, I have had to change them from almost the moment I put them in. I had the new ones tested prior to leaving the store, and it looked like it tested good under load. I drove about 6 miles on Sunday after installing and did show about 13.5 volts. Thought my troubles were over, until I started this morning and showed only 10.4 volts......Is there something wrong with my car that would cause it to fry alternators....???? Is this even possible?

 

[wallyknoch]

I was trying to figure out what I should do for a response to your problem. Alternators and starters are part of our business. But 4 alternators bad? $75.00 for a good alt is very cheap. Poor quality is often shielded with a so called lifetime warrantee. Once hooked you can`t normally get out of the deal and they just keep pushing another alternator at you. Go back as a reasonable person and request your money back plus the core value because most are sold exchange and another parts store will want the core or it`s value.
I don`t know whats in your area to recomend any thing out side of a GM dealer. If you were in my area I would have gladly checked your car for you. good luck,

 

[KOPBET]

Do you have a battery charger? With 10.5 volts at the terminals, I'm thinking possibly a shorted cell in your battery. Remove the battery and put the charger on it. Does the charging current go way high and stay there? What does the battery voltage read before and after charging?

 

[jpanek]

How about your battery and cable condition? If the battery is old and has a high internal resistance or if you have corroded connections (at both battery and alternator, positive and ground sides) then the alternator has to run continuously at max current and burns out quickly. Some shops will not even replace an alternator without replacing the old battery at the same time.

 

[3sacrwd]

Thanks for the reply. I appreciate the help. Is my car frying these alternators? or do you think they are just cheaply made? I know they really don't have much going to them, excpet the 12 V wire, and to have them fry in only a 6 mile (or less) drive seems pretty strange. The other alternators didn't even last that long. I would put them in, and they would not put out more than 11 volts to begin with......I will pull the alt and take it back for another bench test. If it tests bad again, I will ask them what they will do for me.

Let me know if anyone thinks it is my demon car frying them.

Thanks

 

[3sacrwd]

My battery is not that old, less than a year. It is a Diehard. It has been drained more than a few time obviously with this ongoing alternator problem. I have had to put a trickle charger on it quite a few times. My old alt. had a slight humming or buzzing noise and I think it was draining the battery. That has gone away now with the new one that doesn't charge anymore. I had Sears do a load test on the batter about 5 months ago, and they said that it charged fine. My connections are all very clean. I have not checked my negative ground to the frame yet, maybe this weekend. Everything else electronically works fine in the car. If the Serp belt is too loose, would that cause the alt. to stop working?

THanks for the help

 

[jpanek]

Next time you take the alternator to be tested, take the battery along as well. Wire brush your cable ends and you'll be good to go!

Another problem is parasitic battery drain. If you discharge the battery very deeply, then even if the battery and cables are in good shape otherwise, the alternator has to run hot to recharge it. Check the drain with the key off - mine is only 12 milliAmps.

No demons in there, just corrosion! Good luck.

 

[Tom73]

C4's have been know to eat alternators. Have gone through several on my 90. You may want to check out the Corvette Clinic in Fla. Chris Petris there has an alternator conversion that is susposed to cure the problems. Go here:

www.corvetteclinicinc.com

and then click on C4 Solutions

Not cheap but Chris (he is an instructor at the Bloomington Gold workshops and writes service how-tos for the vette magazines) assured me this was the only way to go.

If mine gives up again then I will probably be going that way.

tom...

 

[jpanek]

Tom73,

Have C4's been eating alternators since the beginning, or more recently as they get older on average? The first would seem like a marginal design, while the second aging connections/replacement batteries.

That looks like a solid alternator at corvette clinic. I'll bet he's upgraded the internals to withstand the higher temperatures of working at max current output. But for my money I'd rather try to fix the easier stuff first. Of course crappy rebuilts could be the root cause, but there are other things to check as well.

Here's a good link with alternator failure modes towards the end.

http://www.batee.com/corvette/dcrg/readerstips/larsstuff/this_tech_paper_will_discuss_sim.htm

 

[jsinga]

My 87 has had 4 alternators in the 9 years I've had it. You can bet a weak battery will eat an alternator. A $75 alt is a cheap one. I know a lot of people will slam Pep Boys but I bought a lifetime alt from them in 95 and they have made it good 3 times. The first one lasted 2 or 3 years and I'm pretty sure I helped go south by letting the car sit up for a couple of month and the battery got down along the way. The last one just died. When I got the first one it was rebuilt. Now they only lifetime warranty BRAND new alternators. I don't know who makes them, they're not AC Delco or Delphi. They run $140 but they keep giving me new ones!
I think I would follow the advice about getting my money back. Take the battery in and get it charged up again for the next one to. If the belt is loose it won't kill the alternator, heat kill it from to much current a slipping belt won't let it work that hard. That's why they went to those belts because they rarely get loose.

JS

 

[mangusta1969]

Dying C4 Alternators

C4 alternators are a pretty weak design in the first place. You should not jump start a dead battery with jumper cables and then rely on the alternator to charge the battery back up. You should slow charge the battery back to life first with a battery charger. Using the alternator to charge a depleted battery up places a heavy load on it, overheating it and you may burn out diodes. Then you end up with a low voltage output, as some have experienced.

To verify your battery is still good and does not have a weak cell, chrge your battery overnight on a two amp charge rate with a regular battery charger ($40-60 Pep boys models work fine). I would not rely on a trickle charger to get a dead or near dead battery charged back up.

With a voltmeter, veryify the voltage when the charger is hooked up and charging the battery. It should be 13.5-14 volts.

After the overnight charge, disconnect the charger and measure the voltage on your battery terminals. This voltage will rapidly decrease for a little while. Note the first voltage measurement (with the charger disconnected, it should be about 13.0-13.2 volts, but may drop down to 12.6-12.8 volts 60 minutes after you have removed the charger).

To verify that you do not have a significant resting current drain on the battery, you can measure the battery terminal voltage at 12 hour intervals (do not start the car or operate any accessories/lights, etc.). If the battery voltage drops more than .02-.05 volts per day, I would be concerned about something inside the car that is draining the battery. There may be a better rule of thumb for voltage loss under storage conditions, but that has been about my experience.

You can also disconnect one of the battery terminals and measure the at rest current draw with a voltmeter/ammeter. Just change to scale to amps or 500 milliamps and connect the probes to the disconnected cable and to the battery post you just disconnected it from. The current draw should be around 50 milliamps or less. Less is better, because your connected up battery will last longer with a lower current draw.

I am not sure what the best alternator is for a C4. Has anyone actually found/used a good heavy duty replacement? The CorvetteClinic link doesn't have any technical details on what they have done to improve the design (perhaps the better cooling fan design helps).

A good alternator will produce about 13.5-13.8 volts with engine rpms above 1500. With a good battery in the car, less voltage means weak or dead diodes inside the alternator.

I went through about 4 alternators on my 86 in 8 years. I could eventually change them in the parking lot of an auto parts store in about 10 minutes. One of my four failures was right after using the alternator to charge up a nearly dead battery just after a jump start.

 

[tyrel]

As others have already said, the alternator on the C4 is prone to failure. I have owned three c4s and have repeatedly dealt with just this issue. A good majority of all my breakdown problems go right back to the alternator. An alternator that isn't working properly will not recharge the battery, which gets successively weaker, overtaxing the alternator even more, then you put in a new alternator which works overtime to recharge the weak battery. It's a vicious cycle.

First off, I would not go with chain-store alternators. Rebuilt alternators are unreliable, I have gone through the same thing and have burned them up repeatedly, they usually last about six-twelve months and then they burn up and leave you stranded on the side of the road.

Knowing the inherent weaknesses of the c4 alternator, I did not even bother with an alternator from the dealer, which would have cost an arm and a leg and presented the same problems down the road. There are several companies that build heavy-duty alternators, even a local company can re-wind your alternator and put in heavy-duty parts. Heavy-duty alternator remanufacturers can be found on the web as well, just go to a search engine and start looking.

I chose a different route, buying a heavy-duty alternator from an Ebay alternator remanufacturer who has a lot of positive feedback. This alternator has performed flawlessly for three years, and it is one less thing I have to worry about. My charging system is in top condition and likely to remain that way for a long time. I said goodbye to those crappy rebuilt alternators a long time ago and I never looked back.

 

[mangusta1969]

Don't tease us

Tyrel, please don't tease us.

What is the name/phone number/web site of the heavy duty alternator manufacturer that you have had good luck with? What is the model number for the alternator that has been bullet proof for you?

Thanks

 

[rrubel]

I went the same route as Tyrel, though the seller might not be the same. TK4Sports@aol.com is who I bought from off eBay; it's a 180 amp rebuilt CS-130 (all new) with a lifetime (whatever that means) warrenty. I think I paid about $130.

[RICHR]

 

[jpanek]

Mangusta,

There is an failure mode that drains batteries that you may not see with an ammeter. One of the computers (engine or abs) shorts and drains internally, but when you disconnect the battery to put in your meter, you reset the computer, and the failure goes away temporarily. That must be a pain to diagnose. You need an inductive clamp meter that you put over the cable without disconnecting it.

 

[mangusta1969]

Computer Drain tip

Thanks for the tip on the computer drain. I have not heard of that one.

However, a clamp on DC ammeter should not be required. You can easily and probably more accurately measure the current drain with a standard in line ammeter. Just be certain that you have both leads of the ammeter connected one to the battery post, one to the battery cable, as you slowly remove the battery cable. When the cable is removed from the post, all of the resting current will continue to flow through the ammeter, just as it was with the direct battery to car cable connection.

 

[3sacrwd]

Thanks for the replies. I will take out the battery this weekend to get it tested. The battery has not run down since last Sunday, so I think itmay be OK. I will let you knowwhat I find out.

 

[KOPBET]

Re: Computer Drain tip

Thanks for the tip on the computer drain. I have not heard of that one.

However, a clamp on DC ammeter should not be required. You can easily and probably more accurately measure the current drain with a standard in line ammeter. Just be certain that you have both leads of the ammeter connected one to the battery post, one to the battery cable, as you slowly remove the battery cable. When the cable is removed from the post, all of the resting current will continue to flow through the ammeter, just as it was with the direct battery to car cable connection.

Just don't forget it is there and try to start the car. Your meter will be toast..