hellasboy

My resetting problem has come back with a vengeance! About a month ago, I noticed that if i had the car on (not running) i could run my stereo for about an hour until my car battery would be nearly dead until i was able to get it running. After i did, the car was fine. About a week ago I could run the car with the stereo on for a half hour before the stereo would go dead, but again, after i got the car running i wouldn't have any problems. Just yesterday I had the car on (not running) for a whopping 2 minutes before the stereo started to quit because of a lack of power. In addtion, the car had a hard time starting. i checked the year old battery, but it was always charged

Me and my bro checked the engine and my bro rubbed his hand accross the top of my alternator... guess what? it had this black wet gunk on it - first thought, power steering is leaking! I'm probably going to go the dealership and have them check out the alternator, but does it seem that the alternator and power steering are the culprits? since i will have to replace the alternator (if it is the case), what upgrades are available? what do i need to do about the power steering pump?

thanks!
-nick

hwallen172

Your experiences fit with a theory I have about the resetting (or "ghost") problem. The only way that excessive resistance in the battery cables can cause a problem is when the cables are carrying current. That fact is a bit obvious since logic would tell you that a cable that carries no current might as well not be there, but my theory is that when the alternator is trying to charge the battery, the excessive resistance of the cables causes a voltage drop across the cable that fools the alternator into thinking the buss voltage is high enough that the alternator lowers his field current which drops his output voltage.

Then, something which changes the electrical load such as hitting the brakes, using the turn signal, or, my favorite, hitting "up" on a window that is already up (locked rotor on a DC motor really draws the amps) occurs. The alternator is not ready to source that kind of load because he thinks that the battery is full, and the battery is not ready to source because he's ready for some charging. The buss voltage takes a nose dive, the panel goes dark, and that wakes up the alternator with a vengance. His field current spikes, and we're back in business.

As far as your diminishing ability to run on battery only, that is characteristic of lead acid batteries. Running them dry diminishes their life on a chemical level. The Optima web site has good information on that subject. You could stretch it out by changing the electrolyte, but you're probably in the market for a new battery.

Disclaimer: While I am an electrical engineer (GA Tech, 1985), my minor was digital signal processing, not power distribution. I don't know much of anything, and I'm frequently intoxicated. Pay no attention to me.

SCV8

I'd had a similar thing happen with a battery/charging system;the battery was on it's way out,the alternator was down a diode,and the volts spiked to try and create some amperage.
That wasn't a very good regulator either.
The freshened alternator put things back in balance.
Italian electrical systems aren't that great.

hellasboy

interesting hwallen172. so for us non-electrical engineers , you think that it is the high resistance cable?(s) so far i've changed my ground cable. what would you reccomend?

SCV8, did a freshened (was it new or ..?) alternator fix the ghosting? how long have you had the new alternator?

i'm learning here and no more than before, but also more confused

Thanks!

lexcoupe94

FYI- when I took out my power steering pump I saw black wet gunk on my alternator, too. As noted before on this board, if the pump leaks, it leaks directly onto the alternator below. After awhile the P/S fluid probably gets all over the alternator brushes and renders them useless. I was lucky in that my alternator doesn't seem to be affected.
Alternators are pretty simple-basically a rotor, brushes and diodes. Technically, it's just an electric motor hooked up in reverse. Instead of applying electrical power to produce rotation, the engine rotates the alternator pulley and it produces electrical power.
When I had my Porsche, the alternator quit working kinda like yours appears to be doing. A new one was $350!! I decided to try repairing it first. I took it to an auto electric shop and they simply cleaned it up and replaced the brushes. Worked like new, and it cost me just $75. Most automotive electrical parts are made by the same few companies-Nippondenso, Hitachi, Bosch, AC Delco etc. I bet you could just get it rebuilt like I did (after fixing the power steering pump, of course).

hellasboy

where did you take your alternator to get it fixed? does it take a lot of know-how to rebuild the power steering or should i just go to a local shop to get it repaired (i usually go to toyexus on broadway and i-25, they do a really good job everytime i've been there, reccomend any other shops?)?

hwallen172

Another member had posted that an Optima yellow top battery along with a big capacitor had fixed his ghosting problem. I think you should get high quality battery of that caliber and clean and tighten all your cable connections when you install it. I'd use a wire brush to brighten up the areas where the ground cable attaches to the chassis and engine block. Those areas look like prime candidates for corrosion. A big cap certainly can't hurt. The stereo places can fix you up with that.

As far as your alternator goes, I'd clean that gunk off with contact cleaner and get it tested. I've rebuilt alternators before, and it's not that hard, but if the power steering fluid has eaten away the insulation of the windings, you might as well get a new or rebuilt one. Diode failure in the voltage regulator is very common, and if it causes an over voltage condition, it will boil the electrolyte out of the battery and shorten its life.

Good luck, buddy.

Bean

iTrader: (1)

there should be an alternator rebuilt place in your area... i live in Podunk, AL and there are 3 here

933005spd

Sorry to hear the ghosts are back in your system. I still haven't (knock on wood) had them return. I am running the upgraded alternator putting out 175amps vs our 90/100 amps.

My old alternator was working fine when I pulled it out a few weeks ago, glad to make you a deal on it.

hellasboy

933305sp, how much did your upgraded alternator cost you? who made it? i'll find out soon what exactly i will do, if i decide to go with a rebuild (or your old alternator) i'll let you know did the yellow top fit easily in your SC? I went to optimas web site and they reccomended the orange top (the polaritys are reversed on my sc, not sure about the 300's). but the orange top isn't a deep cycle battery.

thanks for all the info hwallen172, i'm going to go ahead and clean off that gunk on the alternator, clean and tighten all the cable connections for now

thanks!

933005spd

It was about 700 bucks. The yellow top fit fine. I did have to 'juggle' the wires a bit - no big deal.

"Be aware of cheap imitations! There is a competitor selling an "upgraded alternator" for less money, which is of much lesser quality! This alternator is manufactured in Japan for Powerhouse / MVP while our competitor uses all-American parts. Don't misunderstand us, we love America, but do you really want a Mustang alternator on your Supra? Because our competitor uses the same parts as Ford SVT does! This is the ONLY one of its kind: an alternator upgrade for the Supra that is powerful enough to run twin electric fans, twin fuel pumps, ignition upgrades, gauges and other such items without draining the battery. Output current on this upgrade is 175 amps as compared to only 100 amps on the automatic supras & only 90 amps on the 6 speed! This gives you the ability to run stereo upgrades as well as the full complement of performance modifications without the need for two batteries. We highly recommend the use of the Optima Deep Cycle battery for maximum performance with this alternator. Includes all brackets, a high output shielded battery cable with 200 amp fuse and one high quality drive belt.
MSRP $829.99 Your Price $699.00 " MVPmotorsports.com

lexcoupe94

As for the power steering pump, check previous posts from me & VQT. He's thinking about rebuilding his pump too. I didn't rebuild mine, I bought a rebuilt one. Wasn't too tough to install. https://www.clublexus.com/forums/sho...threadid=23609
If you decide to tackle these jobs yourself, I'd recommend having the alternator tested like Hwallen says. The shop will be able to tell right away whether it's just the brushes or what. If you are near the Denver area, try Havana Auto Electric on 14th & Havana in Aurora. That's who fixed my Porsche alternator. When they showed me what they had done, it was apparent that I could easily have rebuilt it myself. If my alternator ever goes out, I would try that first. All the separate parts including brush assembly and diodes are available from Parts.com or your local Toyota/Lexus dealer. Parts.com even has a cool exploded picture of the alternator so you can see what you'd be in for.