Alternator woes...

[sperry]

I think it's time for a new alternator in the SVX.

Unfortunately, I just replaced it not all that long ago with a remanufactured unit from Napa. In fact the one I got from Napa never really worked all that well as within a year I was back to dealing with dead batteries.

So first off, is my problem just the alternator? I know I had some electrical problems in the car due to a short in my remote start harness... but I'm 99.9% sure all that's totally taken care of. Right now, my voltmeter (built into my radar detector, so I'm nearly always watching it) reads about 11.7V at idle and 13.2V at speed. If I charge the battery overnight, I'll get maybe .5V more out of the system, but not for long. And after a week or so, I start running into issues like not being able to start it (just get a single click from the starter and no attempt to turn over). And eventually, the car even starts to drive a little "off"... seems down on power and makes gearshifts at odd times.

I'm pretty sure my issue is just a bad alternator masked by running a good spiral-cell battery. But perhaps the starter is going too?

Does anyone have a good recommendation for remanufactured starters and alternators? I think I'm going to avoid Napa this time around... since the one I've got now is only like a year old and giving me issues (not to mention the 1st one I got from Napa was totally seized and wouldn't spin and needed to be exchanged right out of the box). Should I just go through Subaru? what about high capacity alternators... any of you audio folks have a recommendation for a >95amp alternators with OEM fitment for an SVX?

[MPREZIV]

AC Delco doesn't often let me down with their parts. They're typically pretty decent parts, and I don't see as many "new failed" parts from them.


No promises, just a suggestion.

[sperry]

Originally Posted by MPREZIV

AC Delco doesn't often let me down with their parts. They're typically pretty decent parts, and I don't see as many "new failed" parts from them.


No promises, just a suggestion.

Anywhere to get 'em in town?

[ScottyS]

That voltage sounds low to me. I would expect it to be charging at 13vdc or more even at idle. That being said, are you sure your battery is OK?

I'd be curious to see battery voltage after bench charging, the same after charging and sitting all night, and the same after charging and sitting in the car all night. Using a multimeter.

It seems like the alternator is the culprit, though, given the voltages.

[Dean]

I agree, those voltages sound low. You could have a shorted cell and/or a bad regulator. A 1/2 decent battery with a full charge should be able to hold over 12.5 volts with a >50 watt headlight across it for at least a minute. A good one for probably 30-60 minutes.

Even float charging on a good battery happens at about 12.5-13 volts and 14-15+ under heavy charging after starting or other heavy discharge.

The fact that the system will go above 13 volts means it is likely not the alternator IMHO.

[A1337STI]

you of course tried turning on the car and disconnecting the battery (positive terminal ) and then check the voltage from the positive terminal ? or at least disconnect the positive from battery and see what your radar says?

or take it out 100% and have it bench tested ? I also suspect battery.

I had a similar issue with my rally car but it was the battery, then later the issue popped back up, but it was some wiring going bad and the alternator is ECU controlled and wasn't charging because of 1 wire connection in the gauge cluster came loose.. (nutty)

[Dean]

Originally Posted by A1337STI

you of course tried turning on the car and disconnecting the battery (positive terminal ) and then check the voltage from the positive terminal ? or at least disconnect the positive from battery and see what your radar says?

or take it out 100% and have it bench tested ? I also suspect battery.

Do not run cars without the battery hooked up unless you like fried electronics. The battery acts as a huge leveling capacitor for the entire electrical system. While most sensitive electronics like the ECU and dash have their own voltage regulators and such, some things can still get toasted. It is just is not a good idea.

[MPREZIV]

^^^what Dean said. That's a NO-NO.

Originally Posted by sperry

Anywhere to get 'em in town?

Yep! The Delco store is over on whateverthehellthatstreetiscalled... Off of Vassar headed Eastbound, it's the street that runs along side of the freeway, just past the overpass. Parallel to Market street, just on the other side of 395.

[khail19]

Originally Posted by MPREZIV

^^^what Dean said. That's a NO-NO.





Yep! The Delco store is over on whateverthehellthatstreetiscalled... Off of Vassar headed Eastbound, it's the street that runs along side of the freeway, just past the overpass. Parallel to Market street, just on the other side of 395.

Matley Lane, I believe.

[bign]

http://www.ncautoparts.com/stores.html

[sperry]

Originally Posted by Dean

I agree, those voltages sound low. You could have a shorted cell and/or a bad regulator. A 1/2 decent battery with a full charge should be able to hold over 12.5 volts with a >50 watt headlight across it for at least a minute. A good one for probably 30-60 minutes.

Even float charging on a good battery happens at about 12.5-13 volts and 14-15+ under heavy charging after starting or other heavy discharge.

The fact that the system will go above 13 volts means it is likely not the alternator IMHO.

The fact that I'm on my fourth optima battery in like three years tells me something is wrong with the charging system. I think the alternator works, just not well. I figured there was something draining the battery while it was off, but I checked that and I'm barely drawing any current for the clock and remote start receiver.

So it comes back to the alternator, which never gave me a problem until my radiator sprung a leak and I was forced to drive for an hour spraying coolant onto it. That made the regulator go out and I replaced it with the Napa part. Ever since then I've been eating red tops. I belief you've got several or them at your house right now. Are they bad?

[Dean]

Yes, they are bad(You want them back or I can just recycle?), and as my first sentence says, it could be a bad regulator.

I am also saying it probably ate another battery. If you can't get the battery above 12.5 volts under load, it is toast as well.

Pep Boys and many other auto parts places will test the alternator and regulator if it is integrated into the alternator for free.

If a new alternator didn't fix it last time, I am not sure another one will.

A quick google search found a "SVX Voltage regulator" part for <$200. Not sure if that means it is not integrated into the alternator or if it is a regulator for a subset of the electrical system, but the regulator could well be the issue and not the alternator.

[sperry]

Originally Posted by Dean

Yes, they are bad(You want them back or I can just recycle?), and as my first sentence says, it could be a bad regulator.

I am also saying it probably ate another battery. If you can't get the battery above 12.5 volts under load, it is toast as well.

Pep Boys and many other auto parts places will test the alternator and regulator if it is integrated into the alternator for free.

If a new alternator didn't fix it last time, I am not sure another one will.

A quick google search found a "SVX Voltage regulator" part for <$200. Not sure if that means it is not integrated into the alternator or if it is a regulator for a subset of the electrical system, but the regulator could well be the issue and not the alternator.

There was no problem with the old alternator, at least not until after the radiator hosed hot coolant on it from Roseville to Sacramento. But event since I replaced it, the car's been eating batteries. So I wouldn't be surprised if my current battery were about dead too... but I know that my problem isn't "the battery"... something's killing them.

And the SVX alternator has an integrated regulator. A complete reman alternator is under $150. The parts from Subaru to rebuild your own is close to $1000. I've got all the instructions for rebuilding it myself, but it's just way easier and cheaper to get a good quality remanufactured unit.

[sperry]

According to the test machine at Pep Boys, the problem is the battery. My guess is that both are bad at this point and the tester can't be sure.

So I replaced the battery (for the 4th time now IIRC), but this time with a regular Bosch battery instead of an expensive Optima or Orbital. The voltmeter is still reading ~11.6V at idle and ~13.0V at speed. Since I was short on time, I didn't have them re-test the car w/ the new battery... I guess I'll have to do that some other time. I bet the test comes back with "regulator bad" the next time around.