alternator going bad

[mandude]

If you are running your audio system with a slightly higher load than you alternator can provide, will/can your alternator go bad as a result?

I'm driving a 2001 Saturn SC2 with two amps, PPI 5440 (440 watts) and an Alpine MRP-F600 (600 watts). Not sure what the actual power draw is on those amps. When I run my sytem hard, there is very little (if any) dimming of lights.

I'm paying $$$ to get my alternator replaced right now, wondering if there is a correlation.

If there is a correlation, would running the Big 3 help the problem, or make it worse?

[ppia600]

Yes, the alternator will die if you are drawing more than its rated current, continuously. The battery will lessen the load at first but eventually the alternator will carry the full load and give out. I've got an excellent + and ground system on mine and can toast my alternator in a heartbeat with the amps I have. I'll eventually get an upgraded alternator, but for now I just keep the volume at a respectable level.

[adelphia83]

It's not too uncommon for GM alternators to give way. I replaced two in two years on my old Saturn (both with new AC Delco replacements), and that was without any amplifiers.

[mandude]

So one vote for "toast it in a heartbeat" and one vote for "they just go bad because they are GM"

Any other thoughts?

[grjr]

well, how many amps is the alt. rated for and how many amps do your amplifiers draw? That's what you need to know to answer your question. What are the amplifiers individually fused at? It could just be a coincidence that your alt. died because they are items that wear out. Of course, if you're amplifiers are too much of a load on the alt. it will stress the alt. components and it can fail.

[DigitalJunkie]

Originally posted by ppia600
Yes, the alternator will die if you are drawing more than its rated current, continuously. The battery will lessen the load at first but eventually the alternator will carry the full load and give out. I've got an excellent + and ground system on mine and can toast my alternator in a heartbeat with the amps I have. I'll eventually get an upgraded alternator, but for now I just keep the volume at a respectable level.

And once you drain the battery,it presents itself as yet another load on the alternator,trying to recharge.

In short,Yes -It sounds like you need a bigger alternator.

[wakibaki]

If you're not flattening your battery over time then the alternator is OK. There's no real problem with drawing down the charge on the battery a bit if it gets recharged, it really depends on the usage. If the total average power draw is more than the alternator produces and the system runs all the time the engine is running then you've got trouble.

It's a judgement call... time was you could have checked the battery condition with a hygrometer, but these days batteries are sealed, so it's probably a question of running a couple weeks with the new alternator and watching for a weak start in the morning.

w

[djQUAN]

Originally posted by ppia600
Yes, the alternator will die if you are drawing more than its rated current, continuously. The battery will lessen the load at first but eventually the alternator will carry the full load and give out. I've got an excellent + and ground system on mine and can toast my alternator in a heartbeat with the amps I have. I'll eventually get an upgraded alternator, but for now I just keep the volume at a respectable level.

hmmm. I have three amps with a main wafer fuse at 150A. my alt is around 65A and I turn up the volume once in a while at night (engine running at traffic stops, voltage sags to 12.2V) but my alt is still working. not sure for how long though. BTW, I replaced the stock batt with a bigger size used for trucks.

[SS64]

Those car usually use Delco's cs 130 or 130D Line. Both are junk. Delco's CS144 line where much better alternators. Most of the time if you can find a 144 series that fits on your car you will have a serious upgrade in power. The 130's are rated at 105 amps and do about 60 when hot. The 144's are rated for 140 amps and do about 100-110 when hot.

[wakibaki]

Originally posted by djQUAN
engine running at traffic stops, voltage sags to 12.2V

Yeah, this sounds a bit alarming if the battery is good, but it's not a hard-and-fast indicator of problems.

Obviously the alternator has less power available when the engine is idling, but this is why the usage is critical. If you're spending a lot of time boulevard cruising in hot weather, and the car has an electric fan then you are more likely to run into trouble than if you frequently travel hundreds of miles at high average speed in cool air.

Power rating of audio equipment does not necessesarily relate to the average power drawn. A 65A alternator will probably run ~65A, but amplifier power outputs are ill defined, and amplifier efficiencies vary widely.

65A at 14.8V is still nearly 1000 Watts. Depending on the automobile, alternator, ancillary equipment fit and how the charging regime operates this may be enough.

This said, if I had installed a load of power-hungry kit in my car and my alternator failed for whatever reason, I would take the opportunity to upgrade now rather than later 'cos in the absence of hard-and-fast information it sounds like a good bet and you might need the power in the future anyway.

w