Alternator troubles on 98 Legacy Outback

[soultron]

Ok, I have to ask, because I think I've searched everything and not found an answer.

Let me simplify this long story.

We have a 98 Legacy Outback 5 speed.

My alternator went bad. It was not making voltage. The indicator in the dash was on. I bought an Autozone one and it was making 11 volts and 30 amps, so I took it back. They gave me another one and my car died the next night after turning on the headlights. It was making about 10 volts.

So they give me my money back ( begrudgingly) and I get one from Napa.

It seems to be making 8 volts. I have a new battery and all wires have continuity.

 

My questions:

Are these alternators really this bad? (likely not)

Is there some computer control I don't know about?

Is there possibly some short in the system?

Where do I go next? :-\

[GeneralDisorder]

Autozone is notorious for crappy alternators.

 

Go to the dealer. They have a reman program and the reman units for some of the mid to late 90's stuff are cheap - like $65 because there was a recall on them at one point.

 

There's some posts around here with part numbers, etc.

 

At least that will rule out the alternator being the problem. The only two brands I trust are OEM and Bosch. I've had good results with both.

 

There needs to be ignition switched voltage on the yellow wire to the alt - have you checked all the fuses?

 

GD

Edited April 24, 2010 by GeneralDisorder

[soultron]

What fuses I should investigate ?

[OB99W]

If, with the engine running, the voltage is higher at the alternator output terminal (heavy gauge white wires) than at the battery, check for a blown fusible link (main fuse box, under the hood).

[Rooster2]

Ok, I have to ask, because I think I've searched everything and not found an answer.

Let me simplify this long story.

We have a 98 Legacy Outback 5 speed.

My alternator went bad. It was not making voltage. The indicator in the dash was on. I bought an Autozone one and it was making 11 volts and 30 amps, so I took it back. They gave me another one and my car died the next night after turning on the headlights. It was making about 10 volts.

So they give me my money back ( begrudgingly) and I get one from Napa.

It seems to be making 8 volts. I have a new battery and all wires have continuity.

 

My questions:

Are these alternators really this bad? (likely not)

Is there some computer control I don't know about?

Is there possibly some short in the system?

Where do I go next? :-\

 

 

Maybe I have just been lucky, but I have had no problem with Autozone rebuilt alternators. I am running one on my wife's car, and after three years, it is still going strong.

 

Since your first one was bad from them, I would have had them put their second one that they sold you on their in store testing machine to verify amp output before installation on your car.

 

Suggest rechecking your wiring. The odds of buying three bad alternators in a row suggest a wiring problem. Check your wiring again for damage or poor connections.

[idosubaru]

aftermarket alternators are often risky. it's easy to get a good one too - but also easy to get a bad one. but three in a row is indeed starting to sound unlikely.

 

i would do some proper testing, shouldn't be hard to tell if it's tested properly. they have machines to bring to your car and test it and the charging system properly. surprised they haven't done that yet. advanced auto parts, and i think autozone and other large chains have the equipment and do it for free.

 

i agree with GD on the OEM units, cheaper and you get Subaru. i think last I checked it was $75 and like the 97 OBW's that had the recall.

[john in KY]

Any chance the balancer pulley is slipping?

[tricked919]

dumb question, but have to ask... is the voltage regulator built into the alternator on these units or is it external?

[Rooster2]

dumb question, but have to ask... is the voltage regulator built into the alternator on these units or is it external?

 

built in!

[Cougar]

With the engine running check the voltage getting to the field on the back side of the alternator. I think it is the white/red wire. You should see close to the battery voltage on that pin if the wiring is ok to that point. If the voltage is low and the warning lamp is on check to see that the light goes off if you disconnect the rear connector to the alternator. If the light stays on then there is a path to ground on that wire that shouldn't be there.

 

If that wire is ok then check the voltage between the alternator output lead and the positive battery post with the engine running and a fair load on the electrical system. There should be very little voltage across that connection if that connection is ok. At idle voltage should be around 12.8 volts with reference to ground if the alternator is good.

[soultron]

Yes, they did check the alternators at autozone, I even had advance check them (and Napa). The first 1 was not making enough voltage and failed at autozone. The second one they gave me failed at advance and napa, but not autozone somehow.

I have been checking the wiring and there was some bad stuff going on with the alternator ground wiring. The wires had been cut at some point and just tied in together. I tried straightening that out by attaching new connectors and now I've even attached a jumper from the alternator ground to the battery. It's still only seeing 11.95 on the battery or straight from the alternator.

I suppose I'll start looking for a garage to take it to. :|