Alternator Problems

[GSJoe]

My friend Matt just called me while on his way back home to Charlotte from a trip to Greenville, SC. The alternator on his '91 ZR-1 has just died, and he's concerned about making it back home. A bigger concern, however, is the fact that this is about the fifth time he's had to replace the alternator in that car in the past two years! Has anyone else experienced an alternator issue like this or does anyone have any knowledge as to why he's having this problem?

[VetteVet]

Without knowing what the failures were, it's hard to say.

I can speak from personal experience, that some of the aftermarket replacement alternators have substantially smaller pulleys on them. That smaller size, combined with the free-revving LT5 makes these alternators spin to the moon and fail in short order if you like to wind your motor up(and who doesn't like to wind up an LT5?)

If Matt's been having bearing or brush/commutator failures, that may be his problem.

Jep

[Marc Haibeck]

Jep has a good point. Always transfer the original pulley to a remanufactured unit if the pulley on the reman unit is smaller.

I have noticed a pattern. It seems that cars that are driven often are less likely to have an alternator problem than low mileage cars that are stored a lot. I believe that the alternator can be damaged from excessive heat if it is used to charge a dead battery. It was not designed for high current output for long periods of time. It was designed to charge the battery between starts and counter the accessory power use.

If the car sits for more than two weeks, a Battery Tender should be used. If a battery maintainer can't be used, the battery should be disconnected and charged before starting the car. I think that a ZR-1 should be jump stared only in an emergency.

Note that the alternator on the LT5 is enclosed in a hot environment under the plenum. On most other cars it is in the open with plenty of air flow over it.

Also, a weak battery makes the alternator work harder because it needs more charging. Keep the battery fresh. They cost much less and are easier to access than an alternator.

[LGAFF]

mine croaked on the 92 this winter; less than 2 years old and less than 400 miles on it...I did swap the pulley; and the battery did croak once and was brought back

[XfireZ51]

I've been running a set of under drive pulleys for the last 4 years. But I drive my car more than 3k miles/yr AND I disconnect the battery during the winter. I did just replace the battery this winter.

[scottfab]

Something that has not been mentioned (but has come up before over the years) is that some auto parts houses will try to unload their smaller units on you. I think the standard C4 is a 105 amp unit and ours is a 120 amp. I ran into this so I simply bought a rebuild kit and kept the original 120 amp diode pack that came in the original one.

The link to the rebuild is on TechNet at:
http://www.zr1netregistry.com/Information/TechNet/tabid/109/articleType/ArticleView/articleId/28/Alternator-Rebuild.aspx

Another difference between alternators is that ours has a threaded mount hole on the back for the stock mini bracket that mounts to the head. The smaller non ZR-1 units don't have this hole and therefore the bracket is useless. I suppose the good news is that without that bracket you can remove the alternator without removing the plenum. There is a TechNet article on that too.

[GSJoe]

Thanks for all your thoughts and suggestions, guys. Matt did make it back home late yesterday, and his ZR-1 is safely tucked in the garage at the moment. Sometime this week he intends to pull the plenum to replace the positive battery cable to the starter. Of course he will have to get another alternator, but I'll suggest we take his broken one apart to try to determine what happened to it. His Optima battery has been questionable for some time now, so I plan to suggest its replacement with a new Interstate battery--the big, heavy-duty, correct one for the ZR-1. I bought one of those for my ZR-1 last year and it's been great. Does anyone have a suggestion as to where to buy the best alternator currently available? I know Matt has used several sources in the past, but every one he's bought has been less than reliable for him. Thanks again for your help with this issue.

[A26B]

REMY rebuilds alternators & starters for virtually all of the major auto parts distributors, Autozone-Duraguard, AC Delco-AC-Delco, Advance-ProForm, OReilly-Ultima, etc. The electronics in the core are tested and if good, will remain as-is in the rebuild. They leave Remy in the customers brand boxes.

Simply put, this means that an alternator core may only be cleaned, inspected and receive new bearings and brushes before going out the door to be sold as "rebuilt." Consequently, the voltage regulator, rectifier, rotor, stator & wiring may not be replaced at all. The ACDelco units that were sold by GM were 100% rebuilds. I'm not sure about the ACDelco units of today.

I recommend buying a 100% new parts rebuild, 124A alternator.

[AT T 2D]

Could it have something to do with the two large amplifiers he has for the audio system? I would think they put quite a load on the alternator, he does like his music loud.

David

[VetteVet]

Could it have something to do with the two large amplifiers he has for the audio system? I would think they put quite a load on the alternator, he does like his music loud.

David

I wan't aware that he had a mondo sound system. That could definitely have a bearing(pun intended) on alternator life.

Jep

[HAWAIIZR-1]

REMY rebuilds alternators & starters for virtually all of the major auto parts distributors, Autozone-Duraguard, AC Delco-AC-Delco, Advance-ProForm, OReilly-Ultima, etc. The electronics in the core are tested and if good, will remain as-is in the rebuild. They leave Remy in the customers brand boxes.

Simply put, this means that an alternator core may only be cleaned, inspected and receive new bearings and brushes before going out the door to be sold as "rebuilt." Consequently, the voltage regulator, rectifier, rotor, stator & wiring may not be replaced at all. The ACDelco units that were sold by GM were 100% rebuilds. I'm not sure about the ACDelco units of today.

I recommend buying a 100% new parts rebuild, 124A alternator.

Jerry,

Not a plug for you directly, but having bought alternators and learning by mistake, I would tell anyone to get their alternator from you or at least that same quality. As you know, a new Z owner in Hawaii (Steven on the Big Island) did so and I told him why mess around and try to save money then have aggravation later to R/R an alternator again even if not that difficult. It is simply not worth messing around with a lot of the other stuff on Ebay or internet when there is a known source like you that will stand behind their product. You really do get what you pay for in this area.

Craig :cheers:

[mlotruglio]

I only have one mega amp :nono:but think about it I took the 4 small ones out for one big one shouldnt that equal out??!!



Could it have something to do with the two large amplifiers he has for the audio system? I would think they put quite a load on the alternator, he does like his music loud.

David

[scottfab]

I only have one mega amp :nono:but think about it I took the 4 small ones out for one big one shouldnt that equal out??!!

Depends, how big is the big one? 500Watt? What size are the fuses in it?

[AT T 2D]

I only have one mega amp :nono:but think about it I took the 4 small ones out for one big one shouldnt that equal out??!!

Sorry to hear you only have one amp, all my cars have at least two.

[GOLDCYLON]

I would recommend taking to a local builder to ensure the internals are ALL replaced to your specifications.

GC

[AT T 2D]

Matt - If my memory serves, the one you currently have is aftermarket. I just heard from my friend that they are still available from GM - CS144, 120amp.

[A26B]

We do stock correct, 100% rebuilt Remy alternators if you prefer.
http://jerrysgaskets.com/store2/root/index.php?main_page=product_info&cPath=11&products_id=577

[A26B]

Jerry,

Not a plug for you directly, but having bought alternators and learning by mistake, I would tell anyone to get their alternator from you or at least that same quality. As you know, a new Z owner in Hawaii (Steven on the Big Island) did so and I told him why mess around and try to save money then have aggravation later to R/R an alternator again even if not that difficult. It is simply not worth messing around with a lot of the other stuff on Ebay or internet when there is a known source like you that will stand behind their product. You really do get what you pay for in this area.

Craig :cheers:

Thanks Craig,
Your ears may have been burning over the last couple of weeks. Steve & I have talked and your name came up several times. He's fortunate to have you to consult. Steve is a real ZR-1 enthusiast and fun to chat with. I appreciate your confidence & referral Craig.... Thank you.

We were on the North Shore from Jan10~20, our annual visit. Sitting at Sharks Cove one Sunday morning having breakfast and saw a lot of really nice cars go by, from 30's hot rods, bucket T's to a new ZL-1 Camaro. What better place to go cruizin' although it would be hard to find a place to stretch the legs of a ZR-1.:dancing

[HAWAIIZR-1]

Thanks Craig,
Your ears may have been burning over the last couple of weeks. Steve & I have talked and your name came up several times. He's fortunate to have you to consult. Steve is a real ZR-1 enthusiast and fun to chat with. I appreciate your confidence & referral Craig.... Thank you.

We were on the North Shore from Jan10~20, our annual visit. Sitting at Sharks Cove one Sunday morning having breakfast and saw a lot of really nice cars go by, from 30's hot rods, bucket T's to a new ZL-1 Camaro. What better place to go cruizin' although it would be hard to find a place to stretch the legs of a ZR-1.:dancing

You're welcome and thanks Jerry. Steve is actually a long time friend of my brother and such a great guy. I was surprised when he said he wanted a ZR-1 since he already has 2 C5s and a Anniversary Ruby C4. I have actually never met him, but looking forward to it when I get back.

Yes, Hawaii does have a lot of nice cars hidden in garages, car ports and under tarps and surprised me too on Cruise Nights or otherwise. You're right about the space to stretch the legs of performance cars and too easy to get caught with no where to run. There are a few spots that some know about that will let you do to at least 160 MPH and that is about it. Maybe that is why in the old days only 1/4 cars were built for short runs; if they bring a race track back on Oahu it will probably only be a 1/8 mile track. Take care and hope to run into you one day on the island during your visits. Craig :handshak:

[bldavis11]

Something that has not been mentioned (but has come up before over the years) is that some auto parts houses will try to unload their smaller units on you. I think the standard C4 is a 105 amp unit and ours is a 120 amp. I ran into this so I simply bought a rebuild kit and kept the original 120 amp diode pack that came in the original one.

The link to the rebuild is on TechNet at:
http://www.zr1netregistry.com/Information/TechNet/tabid/109/articleType/ArticleView/articleId/28/Alternator-Rebuild.aspx

Another difference between alternators is that ours has a threaded mount hole on the back for the stock mini bracket that mounts to the head. The smaller non ZR-1 units don't have this hole and therefore the bracket is useless. I suppose the good news is that without that bracket you can remove the alternator without removing the plenum. There is a TechNet article on that too.
The link on the registry site doesn't seem to work. Can you point me in the right direction on how to rebuild our alternators?

[scottfab]

The link on the registry site doesn't seem to work. Can you point me in the right direction on how to rebuild our alternators?

Yes, I see that link is broke. Try this.

http://www.zr1netregistry.com/Information/TechNet/%5BAllArticles%5D/tabid/262/articleType/ArticleView/articleId/28/Alternator-Rebuild.aspx

I am not sure why but this is the second link I've found that is broken this week. I'll investigate..

[bldavis11]

Yes, I see that link is broke. Try this.

http://www.zr1netregistry.com/Information/TechNet/%5BAllArticles%5D/tabid/262/articleType/ArticleView/articleId/28/Alternator-Rebuild.aspx

I am not sure why but this is the second link I've found that is broken this week. I'll investigate..

Scott,

Still no joy. The above link redirects me here:

http://www.zr1netregistry.com/Information/TechNet/%5BAllArticles%5D.aspx (http://www.zr1netregistry.com/Information/TechNet/%5BAllArticles%5D.aspx)


Ben

[scottfab]

Scott,

Still no joy. The above link redirects me here:

http://www.zr1netregistry.com/Information/TechNet/%5BAllArticles%5D.aspx (http://www.zr1netregistry.com/Information/TechNet/%5BAllArticles%5D.aspx)


Ben


Well the Alt rebuild is on that page but.....
if you act quickly this one may work for a few hours
http://www.zr1netregistry.com/Information/TechNet/%5BAllArticles%5D/tabid/262/articleType/ArticleView/articleId/28/Alternator-Rebuild.aspx

Something is changing and changing a lot. Please stand-by

[WVZR-1]

There's a quite good 2 part you-tube for the CS144 alternator build:

http://www.youtube.com/watch?v=riYZssdSmXY

http://www.youtube.com/watch?v=vKbX7mezuFM

I've not watched these in quite some time but I believe it's quite informative.

[bldavis11]

Well the Alt rebuild is on that page but.....
if you act quickly this one may work for a few hours
http://www.zr1netregistry.com/Information/TechNet/%5BAllArticles%5D/tabid/262/articleType/ArticleView/articleId/28/Alternator-Rebuild.aspx

Something is changing and changing a lot. Please stand-by
Well, I missed it. I guess I'm mostly interested in where to purchase a rebuild kit (if available). I can probably work my way through the rebuild after looking at the parts in the kit.

[bldavis11]

There's a quite good 2 part you-tube for the CS144 alternator build:

http://www.youtube.com/watch?v=riYZssdSmXY

http://www.youtube.com/watch?v=vKbX7mezuFM

I've not watched these in quite some time but I believe it's quite informative.

Those videos are invaluable. Holy smokes! Thanks for sharing them!!

:saluting:
Ben

[scottfab]

Well, I missed it. I guess I'm mostly interested in where to purchase a rebuild kit (if available). I can probably work my way through the rebuild after looking at the parts in the kit.


The part number is right there on one of the pics.
http://www.zr1netregistry.com/Portals/0/Images/TechArticle/AlternatorReplace/MVC-392S_JPG.jpg

Looks like depending on the browser you use the link is different.
This works for IE
http://www.zr1netregistry.com/Information/TechNet/%5BAllArticles%5D.aspx
and this for Firefox
http://www.zr1netregistry.com/Information/TechNet/%5BAllArticles%5D/tabid/262/articleType/ArticleView/articleId/28/Alternator-Rebuild.aspx

[WVZR-1]

Well, I missed it. I guess I'm mostly interested in where to purchase a rebuild kit (if available). I can probably work my way through the rebuild after looking at the parts in the kit.

** I don't believe the kit in the image is for a CS144, not knowing the source of the thread with the image mentioning the rebuild but earlier in this thread Scott mentions only using a "portion" of the kit. I'd say that part number is NOT a "wise buy"!

Using that part # and doing some searching I believe if I were doing a rebuild and was interested in a quality build I might source the parts differently. Don't know but the part # or the kit doesn't display a voltage regulator. If there's a reputable automotive alternator/starter shop in the area I'd have a conversation there. Is there someone that does the municipal fleet work, fire ems services

An acquaintance was looking for an alternator a couple weeks ago and I suggested that if his were original I'd repair his rather than buy any "off the shelf" reman and he took his to a shop in the area and less than $25 he was out the door with an alternator repair. NOT a "rebuild" but a repair!

The bearings are very common and quality bearings can be purchased through most local bearing sources, there's cheap and there's quality. A kit that sells for the Amazon price and is in "multi-lingual" packaging has "other than quality" written all over it. There's quality bridge rectifiers and there are quality regulators also. I'd think I'd certainly shop and have a serious conversation before jumping on a "kit"!

[ZZZZZR1]

Using that part # and doing some searching I believe if I were doing a rebuild and was interested in a quality build I might source the parts differently. Don't know but the part # or the kit doesn't display a voltage regulator. If there's a reputable automotive alternator/starter shop in the area I'd have a conversation there. Is there someone that does the municipal fleet work, fire ems services

An acquaintance was looking for an alternator a couple weeks ago and I suggested that if his were original I'd repair his rather than buy any "off the shelf" reman and he took his to a shop in the area and less than $25 he was out the door with an alternator repair. NOT a "rebuild" but a repair!

The bearings are very common and quality bearings can be purchased through most local bearing sources, there's cheap and there's quality. A kit that sells for the Amazon price and is in "multi-lingual" packaging has "other than quality" written all over it. There's quality bridge rectifiers and there are quality regulators also. I'd think I'd certainly shop and have a serious conversation before jumping on a "kit"!

Dave

Where would you recommend purchasing a kit and what kind?

I have a spare kit and like to rebuild it to OEM specs

Thanks!

David

[WVZR-1]

Dave

Where would you recommend purchasing a kit and what kind?

I have a spare kit and like to rebuild it to OEM specs

Thanks!

David

You have a spare "alternator" not kit? The "acquaintance" I mentioned was in Brookville PA and they have a local facility that I understand is well thought of.

In your area I'd think there are several. A local audio shop might have a local shop that they recommend for high amperage builds but you're not interested in all of that or "maybe" you are. I'd think you only need parts! Bearings are easy, there's choices in bridge rectifiers and regulators. Which alternator do you have by part number?

[scottfab]

I had forgotten that I did not use all the parts in the kit.
Did not use the regulator nor diodes.
The life of such components is measured in 100s of years.
There are those that maintain a "quality" rebuild requires such
be replaced. I don't. Proof so far is that my alternator is still working
after a decade.

As far as the bearings go? Well a decade is not bad for a package that
has more than one language on it. Oh well, you mileage may vary.
Just make sure to inspect them (spin them) before installing no matter
what supposed quality you think you're buying.

It's really not hard to fix these alternators.

[bldavis11]

I had forgotten that I did not use all the parts in the kit.
Did not use the regulator nor diodes.
The life of such components is measured in 100s of years.
There are those that maintain a "quality" rebuild requires such
be replaced. I don't. Proof so far is that my alternator is still working
after a decade.

As far as the bearings go? Well a decade is not bad for a package that
has more than one language on it. Oh well, you mileage may vary.
Just make sure to inspect them (spin them) before installing no matter
what supposed quality you think you're buying.

It's really not hard to fix these alternators.
I know at a minimum the bearings are shot. I'm a victim of my own bad judgement. When replacing the fuel injectors a year ago, I had the alternator rebuilt since it's totally stock, was acting kind of weak (lights would dim at idle), and it was easy to get to. After putting everything back together, it doesn't charge the battery now.

I've since moved to a new state and started a new job. In the mean time the Z has just sat. Now I have time to get things right, and the alternator is back out of the car.

None of the local shops around here rebuilds alternators, nor do they know anyone who does. They all just purchase new ones. After taking the alternator down to the parts store for a free test on their bench, I know a minimum the bearings are bad (squealed loudly!). They gave me a print out of a bunch of numbers, but I don't know how to interpret them. Given that, I figured I would take it apart and start replacing things. Sounds silly, but that's what I'm left with.

[scottfab]

I know at a minimum the bearings are shot. I'm a victim of my own bad judgement. When replacing the fuel injectors a year ago, I had the alternator rebuilt since it's totally stock, was acting kind of weak (lights would dim at idle),

Judgement was not so bad. Their execution was. Lights dimming can also be a sign of a bad battery or faulty ground. (the latter being very hazardous to the car electronics.)

and it was easy to get to. After putting everything back together, it doesn't charge the battery now.

I've since moved to a new state and started a new job. In the mean time the Z has just sat. Now I have time to get things right, and the alternator is back out of the car.

None of the local shops around here rebuilds alternators, nor do they know anyone who does. They all just purchase new ones. After taking the alternator down to the parts store for a free test on their bench, I know a minimum the bearings are bad (squealed loudly!).

The rear bearing is what failed on mine. Nothing else was bad but I replaced the brushes while in there and etc.

They gave me a print out of a bunch of numbers, but I don't know how to interpret them. Given that, I figured I would take it apart and start replacing things. Sounds silly, but that's what I'm left with.

Go for it. With the videos given and the link to the ZR-1 page you should be fine. As you may know our Alternator has a higher current output than the standard Alternator of the period. ALSO it has a mounting hole on the back shell that other alternators do not have. Keep your original alt. They are not easily found and when you do you may get one WITHOUT the mounting hole !!!