Brad90

First off I should point out that my power steering reservoir has been leaking for about a week now and I found out it was due to the o ring in my reservoir cap.. and as luck would have it, it leaked on and in my alternator.. So as I'm driving back from work today my check gauges light comes on.. I didn't see my battery was only pushing 8 volts.. and the my airbags light came on then coolant and others came on after.. then my stereo system *** on and off.. and then I lost complete electrical power but luckily I babied the peddle enough and just right to get me home..

So.. I've since taken the alternator off, got it tested twice and it tested perfectly fine.. I cleaned the connectors, put it back in and jumped it off. Drove around and sure enough it happened again..

Any thoughts on what it could be??

1 FMF

iTrader: (1)

the electrical system needs over 10 volts to operate effectively. when voltage drops down around 8 volts like you mentioned, various things stop working because voltage isn't high enough.
so it sounds like (a) your alternator is not charging while installed in your car, and (b) your battery is definitely weak and with the alternator not charging in the car the battery can supply only so much before it goes dead.

my guess regarding (a) is your 4-pin plug that has the one small wire on it which plugs into the top of the alternator is bad, so it's not receiving a signal from the PCM to charge. might have been from power steering fluid, when they hooked that up at the store to test alternator then their connection was good.
it is also possible since you ran your battery down to basically zero that it's now bad and possibly not taking a charge. so at least take the battery out of the car and put it on a battery charger and see if it takes and holds a charge. otherwise put in a new battery.

wssix99

iTrader: (5)

The cap is not tightly sealed. That o ring is jut to keep sloshing fluid in. When was the last time you changed the P/S fluid? It's probably old.


Not a problem. The internals of the alternator are sealed and it gets all sorts of dust, oil, and other nasty stuff up in there through normal use.


As 1 FMF pointed out, the exciter wire is a good place to start. Have you changed anything in the engine compartment recently that might have cut it?

neverlift17

Not a problem. The internals of the alternator are sealed and it gets all sorts of dust, oil, and other nasty stuff up in there through normal use.

are they all sealed? when mine leaked i went through 3 alternators in a few months. I kept having them rebuilt and finally the guy rebuilding them noticed the power steering fluid.

That_One_Person

iTrader: (4)

Same here, but my brother's 2000 T/A went through two in about two weeks because of a faulty P/S pump.

wssix99

iTrader: (5)

Re-man alternators are often garbage. I think the P/S fluid thing is a convenient excuse for poor quality because I have yet to see a good technical reason for how P/S fluid could damage an alternator.

When the windings are re-done, they should be dipped in varnish or epoxy to protect them from contaminants and shorts. From there, it's just the winding and magnets doing a dance. Oil and contaminants should not get in the way of that.


Did he say what the real issue was? Was the fluid eating away the winding coatings? (If so, he was probably not using the right coating.) All the electronics in addition to the winding are also in sealed packages.

Maybe really old P/S fluid with some metal shavings in it could cause some shorting somewhere, but the electronics inside should also be protected from that.

neverlift17

Well i had the original one on when the ps started leaking on it it went out at about 60K. I bought a new alternator from napa and that one went out about 2 weeks later and i didnt have money to by a new one so i had it rebuilt it twice. Its been about 5 years since this so i honestly dont remember exactly what he replaced. All i know is that until i fixed my power steering pump my alternator would go out rebuilt or not. Once i fixed the power steering pump it has worked since and its been about 5 years. There was no metal shavings because i kept putting new fluid in it it was just milky from the air getting into it past the o ring between the reservoir and pump. I dont know what exactly it was caused my alternator to do could. I know mine was leaking like a fossett so it was in it, on it, and through it. Could it cause the alternator to overheat by trapping the heat?

wssix99

iTrader: (5)

I'm not sure that's a strong correlation. I bathed my alternator in fluid when a hose popped off 5 years ago. The entire tank drained on the alternator and its still going strong. If P/S fluid actually ruined these things, mine would have died by now.


Probably not. The alternator has a fan built in to it that continually pumps air through the unit. Any heat would transfer through the fluid or contaminants.

1 FMF

iTrader: (1)

there's a set of brushes that ride on the armature commuator within the alternator, without going into detail they make an electrical connection and if oil or something coats the commutator- oil is an insulator and will prevent the alternator from working. i agree with what was said, everything inside the alternator is basically sealed and solid state minus the brushes. if you were to pull your alternator apart and clean the oil out it would most likely work. i've had alternators under water in boats plenty of times, and that generally doesn't kill them.