'85 Alternator Problem
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Instructor
Joined: Oct 1999
Posts: 145
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From: San Francisco, CA, USA
'85 Alternator Problem
I just put in a new Delco alternator into my 85 about 4 weeks ago. Everything was working well. I've been traveling in San Diego for the last week and just yesterday, I was on the highway and smelled a brief whif of hot electricals. When I left the highway and the fans came on, my volts immediately dropped to sub 12 volts and within a minute the red warning light came on. Is this a problem with the regulator? It sorta seems that way.
Since I'm traveling, I don't have all my manuals and stuff, but I think I can just change out the regulator without replacing the alternator? Any advice would be greatly appeciated. Also, if this does turn out to be the regulator, is it a straigh forward pull and replace? I'm staying with my daughter at my parents house, so I at least have some facilities so I'm not TOO worried. Thanks again for any help...
Since I'm traveling, I don't have all my manuals and stuff, but I think I can just change out the regulator without replacing the alternator? Any advice would be greatly appeciated. Also, if this does turn out to be the regulator, is it a straigh forward pull and replace? I'm staying with my daughter at my parents house, so I at least have some facilities so I'm not TOO worried. Thanks again for any help...
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Re: '85 Alternator Problem (OnDVirg)
Hmmm, it could be the alternator, or maybe the fusible link has taken a dump.
You can pull out the alternator, and take off the (i think its 4) bolts on the back of the 85's alternator. Inside youll see the small regulator and it can be replaced by itself. I'd take it to an auto store and have them put it on the machine to check it out, maybe something else inside it went out.
You can pull out the alternator, and take off the (i think its 4) bolts on the back of the 85's alternator. Inside youll see the small regulator and it can be replaced by itself. I'd take it to an auto store and have them put it on the machine to check it out, maybe something else inside it went out.
Team Owner
Joined: Mar 2001
Posts: 54,124
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From: Cincinnati, Oh USA
Re: '85 Alternator Problem (OnDVirg)
The red warning light comes on when the alternator is not charging the battery. A voltmeter on the alternator output with the engine running will tell if it is the alternator because it should read 14.7 v cold / 13.7 hot. The battery terminals should read the same and if not, the fusible link in the alternator output is open circuit and needs to be replaced. Also, there should be 12v on the red wire on the alternator connector or its fusible link is open and should be replaced.
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Instructor
Joined: Oct 1999
Posts: 145
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From: San Francisco, CA, USA
Re: '85 Alternator Problem (jfb)
A little update on my problem. Hopefully it might help someone else in the future.
Well, after having a couple alternators tested and found good, a trip to the dealer and three days of wondering, I tracked down my charging warning light problem....
I decided since my problem showed up when the fans were running, maybe it had something to do with them? I realized I couldn't hear the aux fan. When I got down and looked, I noticed that I had sucked in a rather large piece of bubble wrap that had wrapped around the fan. This caused it to jam up and I assume overload the electrical. I can't believe the dealer didn't try looking there (actually, me too), but that's why I hate to take the car in.
Oh well...
Well, after having a couple alternators tested and found good, a trip to the dealer and three days of wondering, I tracked down my charging warning light problem....
I decided since my problem showed up when the fans were running, maybe it had something to do with them? I realized I couldn't hear the aux fan. When I got down and looked, I noticed that I had sucked in a rather large piece of bubble wrap that had wrapped around the fan. This caused it to jam up and I assume overload the electrical. I can't believe the dealer didn't try looking there (actually, me too), but that's why I hate to take the car in.
Oh well...
Team Owner
Joined: Mar 2001
Posts: 54,124
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From: Cincinnati, Oh USA
Re: '85 Alternator Problem (OnDVirg)
A stalled fan motor draws a lot of current, maybe not enough to blow the fusible link , but enough to overload the alternator and the battery will then pick up the extra load making the battery voltage drop. You might call the dealer and tell them what you found and recommend they start looking at the aux fan when they have cars with similar symptoms.
