Charging problems
Thread Starter
Instructor
Joined: Jun 2003
Posts: 193
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From: Central Ill
Charging problems
I have an 89 coupe and noticed that the alt gauge was reading low a around 11.1 or less and seemed to be getting wrose so i removed it ( ALTNERATOR ) and had it checked and it was bad. So i replaced it with a new one and not a rebuilt one as i had lifetime replacement. Put new one on let it run showed reaqding of 13.8 to 14.3 right after start up and dropping to around 12 .4 after warmup. Went to go for a ride, three blocks later gauge starts going down by the time i get back home reading is down to 10.6. Take it off and have it tested it is bad so get another one put it on start car reading is at 11.8 to 12.2 at fast idle. Take it off have it checked it is bad. Get another new one put it onstart car it shows 11.8 to 12.5 take it off to get another one. Just need to know if i am overlooking something here. By the way i have had the battery checked and it is good, see no smoke from any wires and smeel no burning of wires. The battery connections are good. There is no drag on the starter. The connection on the starter is good. could i have gotten three bad alternators or should i look for some other problem.
Last edited by BOTY79; May 2, 2012 at 11:36 PM.
Le Mans Master
Joined: Aug 2007
Posts: 8,735
Likes: 412
From: WV
I have read your post twice....Are you talking about replacing your Alternator or your Starter??. The starter wouldn't give you a low amp reading , the alternator would...
.You say you replaced it ...What is the it, alternator, starter, or gauge.???.WW
.You say you replaced it ...What is the it, alternator, starter, or gauge.???.WW
Last edited by WW7; May 2, 2012 at 07:59 AM.
Burning Brakes
Joined: Nov 2011
Posts: 841
Likes: 1
I have an 89 coupe and noticed that the alt gauge was reading low a around 11.1 or less and seemed to be getting wrose so i removed it and had it checked and it was bad. So i replaced it with a new one and not a rebuilt one as i had lifetime replacement. Put new one on let it run showed reaqding of 13.8 to 14.3 right after start up and dropping to around 12 .4 after warmup. Went to go for a ride, three blocks later gauge starts going down by the time i get back home reading is down to 10.6. Take it off and have it tested it is bad so get another one put it on start car reading is at 11.8 to 12.2 at fast idle. Take it off have it checked it is bad. Get another new one put it onstart car it shows 11.8 to 12.5 take it off to get another one. Just need to know if i am overlooking something here. By the way i have had the battery checked and it is good, see no smoke from any wires and smeel no burning of wires. The battery connections are good. There is no drag on the starter. The connection on the starter is good. could i have gotten three bad starters or should i look for some other problem.
Thread Starter
Instructor
Joined: Jun 2003
Posts: 193
Likes: 0
From: Central Ill
Man!! I thought I had bad luck!! Thats very unusual to say the least. To ask if it's possible to get that many bad altenators, in this day of Mexico junk I'd say yes, especially if they came from the same parts house. But I would think the odds of that are really slim to say the least. I've changed a million alts and can't really think of anything that would keep killing them like this. Maybe the builder kept forgetting to put the grease on the regulator? Try a different store in the same chain. You got me curious about this one.
Burning Brakes
Joined: Nov 2011
Posts: 841
Likes: 1
I have had this work for me; see if you have a local rebuilder (almost every area has one) and go there and explain your problem and see if they'll sell you a regulator for that altenator for a couple of bucks and put it in your old one, if you bought a new one you shouldn't have needed to give-up a core and should have it. Take it apart, put in the regulator with dialectric grease and see what you get.
Thread Starter
Instructor
Joined: Jun 2003
Posts: 193
Likes: 0
From: Central Ill
[QUOTE=caddyboy84;1580708079]I have had this work for me; see if you have a local rebuilder (almost every area has one) and go there and explain your problem and see if they'll sell you a regulator for that altenator for a couple of bucks and put it in your old one, if you bought a new one you shouldn't have needed to give-up a core and should have it. Take it apart, put in the regulator with dialectric grease and see what you get.[/QUOT
Long story short i don't have a core ( but i am looking in my garage to see if i had another one).
Long story short i don't have a core ( but i am looking in my garage to see if i had another one).
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Thread Starter
Instructor
Joined: Jun 2003
Posts: 193
Likes: 0
From: Central Ill
No to all the above, I made sure on the second alt that everything was off that i could turn off to make sure there was no drain on the system other than what is used to start car.I have also had battery checked out and it is fine and will hold a charge.And when you start the car it fires right away.
Burning Brakes
Joined: Nov 2011
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Race Director
Joined: Apr 2002
Posts: 10,036
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From: Anaheim CA
I did get a rebuilt alternator that was bad right out of the box, and I have heard of that happening to other people. The last one I bought I had them test in the store before I accepted it. It's a lifetime warrantee but the ink on the thermal paper the receipt is printed on faded so much you can barely read it.
Thread Starter
Instructor
Joined: Jun 2003
Posts: 193
Likes: 0
From: Central Ill
[QUOTE=WW7;1580715472]Your battery has to be at full charge when you install an alternator, if its not at full charge you can blow the diodes in the alternator...WW[/QUOT
I have checked battery voltage before each time i have replaced alternator and it is around 12.6. Also had taken battery in to have it checked and they say ti is good .Although it is four years old.
I have checked battery voltage before each time i have replaced alternator and it is around 12.6. Also had taken battery in to have it checked and they say ti is good .Although it is four years old.
Thread Starter
Instructor
Joined: Jun 2003
Posts: 193
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From: Central Ill
Pro
Joined: Mar 2000
Posts: 658
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From: Perth Amboy New Jersey
I have an 89 coupe and noticed that the alt gauge was reading low a around 11.1 or less and seemed to be getting wrose so i removed it ( ALTNERATOR ) and had it checked and it was bad. So i replaced it with a new one and not a rebuilt one as i had lifetime replacement. Put new one on let it run showed reaqding of 13.8 to 14.3 right after start up and dropping to around 12 .4 after warmup. Went to go for a ride, three blocks later gauge starts going down by the time i get back home reading is down to 10.6. Take it off and have it tested it is bad so get another one put it on start car reading is at 11.8 to 12.2 at fast idle. Take it off have it checked it is bad. Get another new one put it onstart car it shows 11.8 to 12.5 take it off to get another one. Just need to know if i am overlooking something here. By the way i have had the battery checked and it is good, see no smoke from any wires and smeel no burning of wires. The battery connections are good. There is no drag on the starter. The connection on the starter is good. could i have gotten three bad alternators or should i look for some other problem.
Race Director
Joined: Dec 2006
Posts: 10,383
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I'm not familiar with the older C4 alts so take this with a grain of salt and in the spirit of cooperation and help with which it is given.
My first two checks would be with key set to run (engine not started). Note voltage at the battery like you did before when you got 12.6v. Then check the big red wire at the alt (the one you bolt on) for the same. If that checks OK then also look for the smaller but still bigger than the other wires in the alt's pigtail. It is red and something like 10AWG. This is the alt's battery sense line. You should find battery voltage there too.
My first two checks would be with key set to run (engine not started). Note voltage at the battery like you did before when you got 12.6v. Then check the big red wire at the alt (the one you bolt on) for the same. If that checks OK then also look for the smaller but still bigger than the other wires in the alt's pigtail. It is red and something like 10AWG. This is the alt's battery sense line. You should find battery voltage there too.
Melting Slicks
Joined: Aug 2008
Posts: 2,082
Likes: 50
From: Palmdale CA
The only way to know the specifics in this case would be to perform an autopsy on the bad units, and this won't happen.
Were is the OP buying his Alternator's.
Le Mans Master
Joined: Aug 2007
Posts: 8,735
Likes: 412
From: WV
not true...alternator will only produce it's max rated current, if a diode cannot handle this (Chinese made) then it is simply bad.
The only way to know the specifics in this case would be to perform an autopsy on the bad units, and this won't happen.
Were is the OP buying his Alternator's.
The only way to know the specifics in this case would be to perform an autopsy on the bad units, and this won't happen.
Were is the OP buying his Alternator's.
Last edited by WW7; May 3, 2012 at 09:30 PM.