Peice of JUNK GM alt.s or what!!
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Member
Joined: Jan 2001
Posts: 448
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From: Bakersfield,ca,us
Car: 91 z82
Engine: 5.0
Transmission: pro-built 700r4: 2400 stall
Peice of JUNK GM alt.s or what!!
I've got to tell you guys that I am sick and tired of replacing my alt. every time I turn around...
I have seriously gone threw 9 or more in the last 3 years...
I got the warrenty so that's no biggie but having to replace it all of the time is really getting on my case
I have had several people "Parts counter guys/Mechanics" tell me that this searies Alt were flawed by design and the bearing were too small for the applacation (not shure what series but stock for a 91 z) and would fail all the time
What have you guys heard??
Both the front and the rear bearing collapse and sink in to the housing causing the fan blades to rub and start throwing sparks
This seems kinda voilent to me
are you having theses kind of problems??
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Hecubus
Check out my new site http://www.geocities.com/hecubus91
91-Z28 305 Tpi "G92" mods-- K$N/Foil/Cat Back 3" Flowmaster/3" High Flow Cat/B&M shifter/ Intrax Springs/ Kyb Shock's-Struts's/Poly Bushings/Hotchkis Strut Tower Brace/Nos Wet Plate System currently ~200hp shot/ 155lph Fuel Pump/ Holly Adj. Fuel Press. Regulator/Digital Fuel,Air-fuel, voltage & Oil Press Guage's/MSD 6al/ Blaster coil/ Optima,Yellow top batt.
"I spent all my money on race cars, beer, and Broads... The Rest I wasted"
I have seriously gone threw 9 or more in the last 3 years...
I got the warrenty so that's no biggie but having to replace it all of the time is really getting on my case
I have had several people "Parts counter guys/Mechanics" tell me that this searies Alt were flawed by design and the bearing were too small for the applacation (not shure what series but stock for a 91 z) and would fail all the time
What have you guys heard??
Both the front and the rear bearing collapse and sink in to the housing causing the fan blades to rub and start throwing sparks
This seems kinda voilent to me
are you having theses kind of problems??
------------------
Hecubus
Check out my new site http://www.geocities.com/hecubus91
91-Z28 305 Tpi "G92" mods-- K$N/Foil/Cat Back 3" Flowmaster/3" High Flow Cat/B&M shifter/ Intrax Springs/ Kyb Shock's-Struts's/Poly Bushings/Hotchkis Strut Tower Brace/Nos Wet Plate System currently ~200hp shot/ 155lph Fuel Pump/ Holly Adj. Fuel Press. Regulator/Digital Fuel,Air-fuel, voltage & Oil Press Guage's/MSD 6al/ Blaster coil/ Optima,Yellow top batt.
"I spent all my money on race cars, beer, and Broads... The Rest I wasted"
Supreme Member
Joined: Jul 1999
Posts: 5,183
Likes: 42
From: Oakdale, Ca
Car: 89 IrocZ
Engine: L98-ish
Transmission: 700R4
Just had it about a week ago, lost the sealed cover first, tried to make it home and then started losing the ball bearings, then the Alternator started arcing within itself, through the mounting bar that connect to the exhaust...from there to somewhere, i don't recall.
Figured it was time to quit watching the fireworks and replace it
It was the original, lated just under 110K miles, I replaced it with a new (not rebuilt) from AutoZone for 129+tax, with lifetime warranty...hopefully it'll last as long as the original..who knows.
But from what I've heard, the "CS" series of alternators were a pooor design in that they ran too warm, causing several problems. Several aftermarket places make a "Supercool" kit for them, I don't know what it entails, look like from the pic's I've seen, the rear housing, bearings and fan are replaced to provide better cooling.
Figured it was time to quit watching the fireworks and replace it

It was the original, lated just under 110K miles, I replaced it with a new (not rebuilt) from AutoZone for 129+tax, with lifetime warranty...hopefully it'll last as long as the original..who knows.
But from what I've heard, the "CS" series of alternators were a pooor design in that they ran too warm, causing several problems. Several aftermarket places make a "Supercool" kit for them, I don't know what it entails, look like from the pic's I've seen, the rear housing, bearings and fan are replaced to provide better cooling.
Joined: Feb 2000
Posts: 1,855
Likes: 13
From: St. Augustine, FL
Car: 89 GTA
Engine: 383
Transmission: 4L80E
Axle/Gears: 12 bolt-3.73
Get one from AC Delco-GM. The ones from the parts stores are junk. I have a friend with an 88 IROC who killed an advance auto parts alternator at the track, we went and got another one with his 'lifetime' warranty, and the first pass down the track, killed the replacement!. I've run original AC Delco-GM stuff on mine with no problems. Find a GM distribution warehouse that sells to the public to avoid the 'dealer markup'.
agree stay away from auto zone and the likes rebuilt parts. they have to have the lifetime replacement because they don't last. if you want a quality long lasting part buy from GM. even going to a junk yard would be no worse than auto zone.
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ICON Motorsports
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Thread Starter
Member
Joined: Jan 2001
Posts: 448
Likes: 0
From: Bakersfield,ca,us
Car: 91 z82
Engine: 5.0
Transmission: pro-built 700r4: 2400 stall
I'm with you guys on the level that I don't go cheep on parts to sacrifice the quality
ALL of the alt.s that I bought and traded in were from Car Quest "A/C Delco alt." and I still have never got them to last up to a year
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Hecubus
Check out my new site http://www.geocities.com/hecubus91
91-Z28 305 Tpi "G92" mods-- K$N/Foil/Cat Back 3" Flowmaster/3" High Flow Cat/B&M shifter/ Intrax Springs/ Kyb Shock's-Struts's/Poly Bushings/Hotchkis Strut Tower Brace/Nos Wet Plate System currently ~200hp shot/ 155lph Fuel Pump/ Holly Adj. Fuel Press. Regulator/Digital Fuel,Air-fuel, voltage & Oil Press Guage's/MSD 6al/ Blaster coil/ Optima,Yellow top batt.
"I spent all my money on race cars, beer, and Broads... The Rest I wasted"
ALL of the alt.s that I bought and traded in were from Car Quest "A/C Delco alt." and I still have never got them to last up to a year
------------------
Hecubus
Check out my new site http://www.geocities.com/hecubus91
91-Z28 305 Tpi "G92" mods-- K$N/Foil/Cat Back 3" Flowmaster/3" High Flow Cat/B&M shifter/ Intrax Springs/ Kyb Shock's-Struts's/Poly Bushings/Hotchkis Strut Tower Brace/Nos Wet Plate System currently ~200hp shot/ 155lph Fuel Pump/ Holly Adj. Fuel Press. Regulator/Digital Fuel,Air-fuel, voltage & Oil Press Guage's/MSD 6al/ Blaster coil/ Optima,Yellow top batt.
"I spent all my money on race cars, beer, and Broads... The Rest I wasted"
Supreme Member
iTrader: (3)
Joined: Feb 2001
Posts: 1,375
Likes: 0
From: Winfield, IL
Car: 91 RS
Engine: 350tpi comming soon!
Transmission: fixed the 700r4 again!
another option that ive though about is getting an alt. with a higher amp output. theres a local company here that does it and i think they cost around 150 or so.
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91 camaro RS
- 305 TBI
Mods: Performer TBI intake, 1" TBI spacer, K+N, jet fan switch ,160 thermo,Accel control module, Jet Stage 2 chip, edelbrock TES headers, Compleate 3" Flowmaster exhaust, Edelbrock springs, KYB struts and shocks, 700R4 built by TSI, SLP tq converter, b+m trans cooler
Soon to come .SLP Posi 323,Spohn LCA's and panhard bar,Ascd ram air hood, Z28 spoiler and grille,white guage faces.
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91 camaro RS
- 305 TBI
Mods: Performer TBI intake, 1" TBI spacer, K+N, jet fan switch ,160 thermo,Accel control module, Jet Stage 2 chip, edelbrock TES headers, Compleate 3" Flowmaster exhaust, Edelbrock springs, KYB struts and shocks, 700R4 built by TSI, SLP tq converter, b+m trans cooler
Soon to come .SLP Posi 323,Spohn LCA's and panhard bar,Ascd ram air hood, Z28 spoiler and grille,white guage faces.
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Hecubus,
Ed and 89GTA have the right idea. The original Delco alternator is just fine, and is probably better than many other designs. The problem is in getting the aftermarket rebuilds, where all the parts are mixed together, cleaned, tested, then assembled. Your "lifetime" rebuilt might have a case that is stamped "104A" but the stator might be from a 63A unit and the rotor might have been from a 90A unit and te rectifier bridge might be from a 47A unit. You're probably lucky to get two case halves that match.
Stay away from these low-quality rebuilds and get another Delco alternator - just like the one that lasted for the first 10-15 years. When it quits again in 10-15 years, repair it yourself rather than exchanging it for a reman that you have no clue about.
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Later,
Vader
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"What a Day..."
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Ed and 89GTA have the right idea. The original Delco alternator is just fine, and is probably better than many other designs. The problem is in getting the aftermarket rebuilds, where all the parts are mixed together, cleaned, tested, then assembled. Your "lifetime" rebuilt might have a case that is stamped "104A" but the stator might be from a 63A unit and the rotor might have been from a 90A unit and te rectifier bridge might be from a 47A unit. You're probably lucky to get two case halves that match.
Stay away from these low-quality rebuilds and get another Delco alternator - just like the one that lasted for the first 10-15 years. When it quits again in 10-15 years, repair it yourself rather than exchanging it for a reman that you have no clue about.
------------------
Later,
Vader
------------------
"What a Day..."
Adobe Acrobat Reader
I too have a ’91 Z28. With close to 100K miles, the only problem I had was one diode in the rectifier assembly went bad at ~60K miles. As has been posted above, CS-130 alternators are known to have a heat problem. The more the alternator puts out, the hotter it gets.
You may want to consider modifying with National Quick Start’s Iceburg’s Alternator kit that tries to overcome these faults (this is what I did). It comes with two bearings. The front bearing is identical to the original. The rear is bigger (10mm) than stock. A new rear housing is included to accept the larger rear bearing and it also has a little more surface area (fins) which will keep it cooler. A new rectifier and brushes are also included. There is no new/additional fan. (Some aftermarket CS style alternators have an additional internal fan to aid in cooling.) It is $50 from Summit or J.C. Whitney.
They also make a high-output kit to boost the output to 140 amperes for $100.
Even with the modified parts, they (National Quick Start) recommend that the alternator does not output a lot of current for a long time. For example they recommend not to charge a dead battery with the alternator for more than 15 minutes at a time. I wonder how worthwhile their 140 ampere modification would be unless the rear housing contains a much larger heatsink than their $50 kit, since this will be generating a lot more heat!
At only $50, it might be worth a try. I haven’t had a problem with mine since, although I only have ~40K miles on it.
You may want to consider modifying with National Quick Start’s Iceburg’s Alternator kit that tries to overcome these faults (this is what I did). It comes with two bearings. The front bearing is identical to the original. The rear is bigger (10mm) than stock. A new rear housing is included to accept the larger rear bearing and it also has a little more surface area (fins) which will keep it cooler. A new rectifier and brushes are also included. There is no new/additional fan. (Some aftermarket CS style alternators have an additional internal fan to aid in cooling.) It is $50 from Summit or J.C. Whitney.
They also make a high-output kit to boost the output to 140 amperes for $100.
Even with the modified parts, they (National Quick Start) recommend that the alternator does not output a lot of current for a long time. For example they recommend not to charge a dead battery with the alternator for more than 15 minutes at a time. I wonder how worthwhile their 140 ampere modification would be unless the rear housing contains a much larger heatsink than their $50 kit, since this will be generating a lot more heat!
At only $50, it might be worth a try. I haven’t had a problem with mine since, although I only have ~40K miles on it.
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They are flawed by design, but it could be that something else is wrong... a weak battery that puts alot of demand on the alternator will kill it. So does bad wiring, bad grounds, etc. Check to make sure all the wires are ok for the charging system, that you have clean connections and a good ground. And check out that battery, it might be on its last leg.
Member
Joined: May 2000
Posts: 419
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From: Parkersburg, IA, U.S.
Car: Trans Am
Engine: L69
Transmission: T5
Axle/Gears: 3.73
Yes stay away from alternators and staters from auto zone ect.. Get a good new Delco.. I have 130,000 and more on delco's still going too... You get what you pay for.. Kevin
Joined: Jul 1999
Posts: 10,950
Likes: 26
From: Orange, SoCal
Car: 1990 Pontiac Trans Am
Engine: 355 TPI siamesed runners
Transmission: Tremec T56
Axle/Gears: 12-Bolt 3.73
I went thru 4 alternators in 2 years. Then I got an LT1 alternator and the bracket to connect it to the TPI stuff. I havent had a problem with it, but its only been 2 months.
Hecubus, have you checked out the local SoCal Thirdgen club?
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West Coast GM Shootout 2001!
1991 Camaro Z28
5.7L 5-Speed (originally 305)
13.25 @ 107.18 MPH
Southern California
Member: SoCal 3rd Gen F-Bodies
Webmaster: SoCal F-Bodies
-=ICON Motorsports=-
Hecubus, have you checked out the local SoCal Thirdgen club?
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West Coast GM Shootout 2001!
1991 Camaro Z28
5.7L 5-Speed (originally 305)
13.25 @ 107.18 MPH
Southern California
Member: SoCal 3rd Gen F-Bodies
Webmaster: SoCal F-Bodies
-=ICON Motorsports=-
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Joined: Feb 2000
Posts: 1,416
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From: Johnstown, Ohio
Car: 84 Z28
Engine: 355 (fastburn heads, LT4 HOT cam)
Transmission: 700R4
Axle/Gears: 9-bolt, 3.27
Are the CS series "rebuildable"? I prefer to rebuild my own, but i started tearing into one and it seems you have to destroy a plastice piece inside to get it apart. I have rebuilt the older SI series (10 and 12) in tyhe past, but these seem to be more difficult.
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Working on:
'84 Z28 LG4 305 with 200,000 original miles!
Added dual elec fans.
145 MPH IROC Speedo
Building 430 HP 350 (ZZ430)
using primarily GMPP parts.
Short block sitting on a stand. (Man, those Fast-Burn heads sitting on it look good!)
Starting to look like the Kicker poster child!
ASE Certified Master Tech
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Working on:
'84 Z28 LG4 305 with 200,000 original miles!
Added dual elec fans.
145 MPH IROC Speedo
Building 430 HP 350 (ZZ430)
using primarily GMPP parts.
Short block sitting on a stand. (Man, those Fast-Burn heads sitting on it look good!)
Starting to look like the Kicker poster child!
ASE Certified Master Tech
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Joined: Dec 2000
Posts: 1,536
Likes: 0
From: Springfield, MO, USA
Car: 1986 Trans Am, 1991 Firebird
Engine: 355 TPI, 3.1L V6
Transmission: 700R4 in both
Of course, I gotta be the differnt one here! I have an alternator from O'reillys!! I'd rather have a lifetime warranty than buy a better quality one with a lesser quality warranty!! In my lifetime that I own the car I will have spent less money than guys who replace with Delco parts!! I spend money for ONE alternator and never again will I have to pay for another alternator...and the one I have is cheaper too! So even if the Delco alt lasts forever I'll still have spent less money!
Of course, I don't have a CS alternator either....and I hear they suck bad! However, my friend has one in his '89 Formula and I believe he had his stock one rebuilt by an alternator shop probably 4 years ago or so and he still hasn't had a problem with it!
I've also heard that it's "possible" for the CS alternator to fry the ECM too if something goes bad in the alternator! Could just be a rumor!!
Of course, I don't have a CS alternator either....and I hear they suck bad! However, my friend has one in his '89 Formula and I believe he had his stock one rebuilt by an alternator shop probably 4 years ago or so and he still hasn't had a problem with it!
I've also heard that it's "possible" for the CS alternator to fry the ECM too if something goes bad in the alternator! Could just be a rumor!!
Thread Starter
Member
Joined: Jan 2001
Posts: 448
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From: Bakersfield,ca,us
Car: 91 z82
Engine: 5.0
Transmission: pro-built 700r4: 2400 stall
I have had a bunch of people here tell me that A guy in town is really good at rebulding them and makeing them heavier duty and what not...
I think I'll give him a visit and see what he can do for me ...I'm shure that if there is a prob with that series that he'll know what to do with it
thanks for the help guys
------------------
Hecubus
Check out my new site http://www.geocities.com/hecubus91
91-Z28 305 Tpi "G92" mods-- K$N/Foil/Cat Back 3" Flowmaster/3" High Flow Cat/B&M shifter/ Intrax Springs/ Kyb Shock's-Struts's/Poly Bushings/Hotchkis Strut Tower Brace/Nos Wet Plate System currently ~200hp shot/ 155lph Fuel Pump/ Holly Adj. Fuel Press. Regulator/Digital Fuel,Air-fuel, voltage & Oil Press Guage's/MSD 6al/ Blaster coil/ Optima,Yellow top batt.
"I spent all my money on race cars, beer, and Broads... The Rest I wasted"
I think I'll give him a visit and see what he can do for me ...I'm shure that if there is a prob with that series that he'll know what to do with it
thanks for the help guys
------------------
Hecubus
Check out my new site http://www.geocities.com/hecubus91
91-Z28 305 Tpi "G92" mods-- K$N/Foil/Cat Back 3" Flowmaster/3" High Flow Cat/B&M shifter/ Intrax Springs/ Kyb Shock's-Struts's/Poly Bushings/Hotchkis Strut Tower Brace/Nos Wet Plate System currently ~200hp shot/ 155lph Fuel Pump/ Holly Adj. Fuel Press. Regulator/Digital Fuel,Air-fuel, voltage & Oil Press Guage's/MSD 6al/ Blaster coil/ Optima,Yellow top batt.
"I spent all my money on race cars, beer, and Broads... The Rest I wasted"
<font face="Verdana, Arial" size="2">Originally posted by Kevin91Z:
I went thru 4 alternators in 2 years. Then I got an LT1 alternator and the bracket to connect it to the TPI stuff. I havent had a problem with it, but its only been 2 months.</font>
I went thru 4 alternators in 2 years. Then I got an LT1 alternator and the bracket to connect it to the TPI stuff. I havent had a problem with it, but its only been 2 months.</font>
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Later,
Vader
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"What a Day..."
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<font face="Verdana, Arial" size="2">Originally posted by JP84Z430HP:
Are the CS series "rebuildable"? I prefer to rebuild my own, but i started tearing into one and it seems you have to destroy a plastice piece inside to get it apart. I have rebuilt the older SI series (10 and 12) in tyhe past, but these seem to be more difficult.
</font>
Are the CS series "rebuildable"? I prefer to rebuild my own, but i started tearing into one and it seems you have to destroy a plastice piece inside to get it apart. I have rebuilt the older SI series (10 and 12) in tyhe past, but these seem to be more difficult.
</font>
The worst part on these alts is the rear bearing, its too small... not only OD like the 'improved' one, but the ID as well. Ford uses the same stupid bearing on their high amp alts, and they have the same problem.
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