Charging system failure, stranded.

[Mephis]

To give you a little back ground with my history with subarus.

I've also got a 91 XT6 in addition to my 92 SVX. On my XT6 any time I used the headlights I'd burn out the fuse for the charging system. Eventually after getting stranded about 100 times I bypassed the fuse at the fuse box and I've never had a problem again, 3 years down the road.


Fast forward to now with my SVX, it only has 63k miles on it and is practically new in every way. I was heading back from king's island amusement park with my GPS plugged in, my radar detector, and my lights/fog lights running. About 50 miles away from the park I noticed on my radar detector it was warning me that my voltage was getting low. Later the ABS light came on, and the Airbag light shortly after. So I got off on an exit as fast as possible, since I was sitting at 8volts left. I had to shut off my lights to get enough power to make it to the gas station across the street.


I'm no stranger to charging system failures. This is only the 213738462871 time this has happened to me, just not with this car. I'm almost 100% positive it's just a fuse, but which one is it and where is it? Also, if you SVX guys know better than my dumb backyard mechanic knowledge and I'm wrong, please point me in the right direction!

[huck369]

Check your crank pulley, paint a mark across the front of it, then start the car, and run it untill it's warmed up.....run the AC, and lights some then shut it off, and see if the inner and outer rings of the pulley are staying aligned....I'm betting it's slipping (coming apart) in which case you need a new pulley (a one piece aluminum one for an Impreza will work, and will keep this from happening again...)

If it isn't the pulley, then you need a new alternator....


(oh year....are you on the www.subaruxt.com board?...sounds like you're not too far away from me...)

[Mephis]

Yea, I'm from the XT6 forums. I'm the guy with the flat black XT6. I live over on the martinsville/mooresville indiana area.

I also have about no money at all right now so I have to do about what ever is cheapest.


That's also exactly what happened on my XT6 too... Never thought of it but sounds about right since I thought I heard something.

[SoCal LS-L]

If your alternator is shot, heres a trick. Start the car, then hit the alternator with something hard with a nice sharp ping. Dont hit it REALLY hard, just hard enough like youre starting a nail, maybe a little harder. You should hear the engine tone change and the alternator should start charging again. I was shown this trick to get me home in high school, and it actually gave me a couple months more use before the light came back on. Ive done this on at least 6 or 7 of my cars. Trust me, this works and will get you home.

[huck369]

Originally Posted by Mephis

Yea, I'm from the XT6 forums. I'm the guy with the flat black XT6. I live over on the martinsville/mooresville indiana area.

I also have about no money at all right now so I have to do about what ever is cheapest.


That's also exactly what happened on my XT6 too... Never thought of it but sounds about right since I thought I heard something.

Cool....you need to bring the XT down this way some time....I'll take you for a ride in FrankenWedge

[Mephis]

Well I rented a trailer and took it up to my local shop since I've just been too pissed off lately to deal with working on anything. (Driving that behind me on a trailer was about as stressful as dangling a baby off a skyscraper) Threw a spare battery in and got it on and off without a problem.

Have an aluminum pulley coming 2 day air.(Funny enough it was cheaper than a factory replacement) I checked it while I was out there and sure enough the pulley had come apart on me. Thanks so much for the help!

And I'll see about getting the XT down some time. I don't have insurance on it or anything right now because it's my winter car, it's also pretty beat to hell but it's the best running and easiest starting thing ever.

[huck369]

Well, at least it will be an easy fix.....

And you can always come down in the SVX too....
We have a big car show the 4th Saturday of every month thru the summer....
If you ever want to come down for that...

[Mephis]

Oh sweet! Yea when I get my SVX fixed I'll head down and check that out.

Probably won't be this month, but never know.

[gbianchi]

There is also wiring problems on some of these svxs that can cause not charging fun, 2days after I got mine the lamos that put in the alternator for the p o biffed the wiring to the alt so they grounded together and nearly melted the main bolt down connector, hot and stinky. A little rewiring and so far all is well.................G

[Mephis]

Originally Posted by gbianchi

There is also wiring problems on some of these svxs that can cause not charging fun, 2days after I got mine the lamos that put in the alternator for the p o biffed the wiring to the alt so they grounded together and nearly melted the main bolt down connector, hot and stinky. A little rewiring and so far all is well.................G

Well it would charge when I revved it, then act like it was slipping, charge some, then stop charging... Etcetcetc. (It also overheated some, telling me the water pump wasn't being turned over.)

The part and the car are both in the shop right now and I'm expecting to get it home tomorrow. I'll let you know what's up when I get it back.

[huck369]

Sounds like the water pump is seizing up....happened on my first SVX too, took out a couple T-Belt pulleys when it finally went....

[Mephis]

Problem not solved. $300 down the drain... (I don't make much so I hope we can figure out what's up cheaper)

I also discovered something else. Engine fans aren't running. Temp gauge isn't showing it's overheating either, even though I know it has to be. The fuses are fine.

Battery isn't charging either. Optimas are good batteries, I drove 25 miles on the battery.



I just looked under the hood for the water pump and I can't even figure out where it is. Also, would the water pump really go out at 62k miles? :\

[SoCal LS-L]

Originally Posted by Mephis

Problem not solved. $300 down the drain... (I don't make much so I hope we can figure out what's up cheaper)

I also discovered something else. Engine fans aren't running. The fuses are fine.

Battery isn't charging either. Optimas are good batteries, I drove 25 miles on the battery.

Some ECU's are programmed to halt cooling fan operation when operating below a certain voltage (such as an alternator failure), to give you more limp-home time.

From your description, I would first trace the main current feed cable from the alternator to the battery and make sure its ok. Then if you want to try something else inexpensive before junking the alternator, run another low gauge wire directly from the alternator post to the positive battery cable where it connects to the battery, and see if it makes a difference.
Lastly, since it doesnt charge at idle, do what I suggested below and whack the alternator with a good hard tap, with a hammer or like, and see if starts charging again. This method resets the brushes and restores the alternator charge field, and might even get you by for a month or so. Hit it square on the metal housing, and when the engine tone changes, you know its charging again. This has worked many times for me on my trucks and my old honda.

[Mephis]

I actually tried wacking the alternator a few times with a hammer and it didn't do anything.

I'm not really clear on how hard to hit it, but I'm sure I hit it plenty hard.

[kwren]

How hard to "whack" the alternator is not an exact science.

The best way might to test the system and see exactly what it is doing?

Keith