92 century alternator replacement

[effedup]

Hi all, new to the forum and got some questions!

I've got a 1992 Buick Century Custom V6 3.3L. It's my daily driver and I love the car to death, so I try to stay up on maintenance. That and I can't afford to get a new one. Here's the situation...

I've replaced my battery 3 times in 5 years, which obviously isn't right. Luckily, since the batts aren't that old, I don't pay much out of pocket to replace them, but it's still annoying. Recently, however, the headlights and instrument lights are flickering (not too badly but enough to be annoying), so I figured my problem was a little bigger than a simple low battery.

Anyways, I had my car in to Midas to get a tune-up, oil change, and spark plug wire replacement, and had them test my alternator. Turns out my alty is starting to go...the power output, which should be constant, is fluctuating up and down, straining the battery. That's probably why my batts only lasted a year or so. I didn't have the money to replace it right then, but had them quote me a price for replacement with a new alty...$175 or so (estimate) including parts and labor.

I've got friends that say this is a pretty easy fix, and taking it in to get it done is a waste of $$$. I priced new altys and they're about $120. I guess my question is, is alty replacement that simple of a process? The friends are willing to help me with it (I'm not mechanically inclined at all), but I'm torn between having Midas do it (and have a warranty on it), or do it ourselves to save 50 bucks. The last thing I need right now is something getting screwed up and having to get the car towed to midas, since im short on cash anyways. Also, I've got a 600watt amp and 2 12" subs, and I'm worried that THEY might be causing problems, straining the alty. All the new altys I priced had the same amperage output, so I want to make sure I don't need a higher output before I buy a new one and have it crap out on me from the strain...or am I worrying needlessly? Like I said, I'm not very knowledgable about cars. Any help is greatly appreciated!

[maxwedge]

Thats a 50 amp load from the audio system! A 100 amp alt, is max output rated, so 50 is gone for the audio, use the lites heater/ac wipers and the alt is on overtime. Look into a 140a alt option. For installation check autozone.com/repairinfo

[effedup]

Wow, I didn't know the amp drew that much power! When I got the stereo installed at Circuit City a couple years ago, the install guy SWORE that it wouldn't be too much for my alt to handle (I was understandably concerned), he said just not to use it with the car off. Guess he was just full of crap. Not that I'm surprised...

I'll go check out the prices of a bigger alt right now. Another question, when they say "7 o'clock" vs "11 o'clock", what does that mean? They've got 2 choices for every model alt and I don't want to get the wrong one...

Thanks!

[maxwedge]

Position of mounting tab ears I guess. You could have someone check the current draw on the battery cable, with the audio on and see what it draws to make sure I am right.

[tri-power]

The 7 or 11 refference could also be the position where the wiring harness connects to the alternator. Make a diagram of where everything is on your current alternator so that you can get the right clocking, or postion. Sometimes the same type of alternator has different positioning or are simply assembled in the wrong position.