high revs needed to trigger alternator

Hi there,
When I start the engine of my 75 camaro, I can see on my amp meter that when started, the battery keeps discharging. The alternator is spinning, and the belt is OK.
Also I notice slow windshield wipers, and slow electric windows.
Only after I rev the engine up to high revs, the charging circuit suddenly kicks in. After that, the battery is being recharged, also at low revs.
I cleaned the contacts on the alternator, and the alternator is only 2 years old or so. Should it be replaced? Can it be refurbished?
thx,
Bram Stolk
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Bram Stolk wrote:

This sounds like it might be a bad regulator in the alternator (I believe they are internal in that year). You can get just the regulator and replace it if you have good mechanical skills, or just replace the alternator. I know they normally last longer than 2 years, but I have seen them last less than a year as well.
--
Cy Welch
89 Camaro RS 5.0 TBI
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Cy Welch wrote:

Hmm... are you sure about the "good mechanical skills" part? I opened it up, and I think that it can only be put together again in the factory. It has a very tricky system of contacts on a spring, pushing against the axle. I dont think you can refit the axle with the contacts in the proper place.
I'll just have to buy a new one then. It is a 3 wire Delco, 15 amps alternator, btw. The 15 amps surprised me, as the year-one replacements are something like 200 amps? Sounds like overkill to me.
Bram

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axle = armature ... contact = the brushs/holder is my guess .. use a toothpick to hold the brush's in place when reassembling the alternator , it's then pulled out when it's back together .. there's a small whole in the alt. case , and brush holder for just this purpose ... be sure to clean up the copper surface that the brush's ride on ( commutator ) ... you can get a brush set for about 5 bucks .... and a 15 amp alt Ώ .. never heard of such a thing ... 35-40 be more like it .. if you go the rebuilt route for about 5 buck's more you can get a 60 amp alt. ... 200 amp is somthing you'd be likely to find in an ambulance or some other severe duty application , not needed to say the least
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The ΗLψne wrote:

Ah!!!!
Yeah.. the shop told me that the 15 amps couldnt be right either. There was a 15A stamped on the casing... I guess it may be a model nr instead.

Well, I got a brand new one, with a little more juice. 70 amps or so. It set me back 166 euros, but what the heck... I'm glad to be driving again. That rumbling free-flowing V8 sounds so sweet, especially when you haven't heard her for a couple of days.
Bram
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Do you have a "one wire" alternator? If not, did the car originally have an alternator lamp in the dash?
Al
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That was the first thing I thought of. I have a one wire alternator on my pickup and it works the same way. It's not really a problem once you understand how it works.
Gary
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