December 30, 200916 yr What gives here... '85 Brat, this seems to be the second alt the car has gone through in the last 6 months. First one that the car came with, started losing the voltage regulation, and would occasionally spike up to 18 volts. Now tonight, while climbing I70, the alt(that is actually a junkyard alt) is basically doing the same thing, only more consistently. It started hitting 18 volts, and would drop down to 13 volts at idle. However, all the red lights stay on now. The voltage, brake, parking, and whatnot lights all stay lit, though dimly, when the car is running now. Bah...
December 30, 200916 yr What gives here... '85 Brat, this seems to be the second alt the car has gone through in the last 6 months. First one that the car came with, started losing the voltage regulation, and would occasionally spike up to 18 volts. Now tonight, while climbing I70, the alt(that is actually a junkyard alt) is basically doing the same thing, only more consistently. It started hitting 18 volts, and would drop down to 13 volts at idle. However, all the red lights stay on now. The voltage, brake, parking, and whatnot lights all stay lit, though dimly, when the car is running now. Bah... I would say that something is going on other than just the alternator failing, and your alternator is gone again... How is your battery? I have seen alternators get fried because of a low charged battery. When the battery is low, the alternator tries to charge it. If it can't charge it for whatever reason, it just keeps on truckin' at full power, eventually wearing it's self out. So I would check/charge/replace your battery. If your battery is good, check all your grounds, corrosion causes resistance, and resistance can fry alternators. Truthfully, I would dump the stock alternator and get a bigger/better one. Nissan or GM, but I would take the time/effort to do it now, and then you won't have to worry about it. This is assuming it's JUST the alternator that went out and that there is no other underlying problem. If there is still a problem, replacing it with a Nissan/GM alternator isn't going to fix it, they will break down as well until the problem is fixed. This of course all costs money...
December 30, 200916 yr Author I would say that something is going on other than just the alternator failing, and your alternator is gone again... How is your battery? I have seen alternators get fried because of a low charged battery. When the battery is low, the alternator tries to charge it. If it can't charge it for whatever reason, it just keeps on truckin' at full power, eventually wearing it's self out. So I would check/charge/replace your battery. If your battery is good, check all your grounds, corrosion causes resistance, and resistance can fry alternators. Truthfully, I would dump the stock alternator and get a bigger/better one. Nissan or GM, but I would take the time/effort to do it now, and then you won't have to worry about it. This is assuming it's JUST the alternator that went out and that there is no other underlying problem. If there is still a problem, replacing it with a Nissan/GM alternator isn't going to fix it, they will break down as well until the problem is fixed. This of course all costs money... Battery is brand spanking new. I bought a new one after replacing the previous alt, as I was unsure of the state the battery would be in. I did check several grounds before, but I will go back at them and make sure everything is good again. I guess I'll swap the alt from the '87 onto the '85 for now, and see if that fixes it. If it does, I guess a Maxima alt is in my near future.
December 30, 200916 yr Battery is brand spanking new. I bought a new one after replacing the previous alt, as I was unsure of the state the battery would be in. I did check several grounds before, but I will go back at them and make sure everything is good again. I guess I'll swap the alt from the '87 onto the '85 for now, and see if that fixes it. If it does, I guess a Maxima alt is in my near future. Well then, it looks like you have done all the "simple" things. I would try swapping alternators like you said and see what happens. Could be you just picked up a bunk used alt from the JY. Good luck!
December 30, 200916 yr the stock craptachi alternator is crap, 40 amps full output, lame.... i notice that if im running the heat full, and the high beams on, and the radio cranked there isnt much left to charge the battery..
December 30, 200916 yr After you install the replacement I recommend you check the voltages of all the leads to the alternator while the engine is running and the alternator is charging. The main output wire should be between 13.5 and 14.8 volts. The wires on the back side should be about the same or slightly lower voltage. Check the voltage between the output wire and positive battery post with a good load on the system. There should be less than .1 volts there if the wire connections are good. The other warning lights you saw on are that way because they are in the alternator field circuit for testing when the key is turned to ON or RUN. When the alternator has trouble those lights can be effected also. You most likely have some bad output diodes in the alternator along with a bad internal regulator. Edited December 30, 200916 yr by Cougar
December 30, 200916 yr Yes - they are crap. Especially the common reman units. But you probably have poor connections somewhere - causing the system to draw harder on the alt to compensate. Check for voltage drop between the alt and the positive battery terminal, and check for drop on the main junction sensor lead. Very often there is a poor connection and this causes constant heavy load on the alternator (it will feel hot all the time). Could also be a poor battery/terminals. GD
December 30, 200916 yr Author Ok, swapped the alts, and that fixed the problem. The alt on the '87 is a reman'd unit. I did remember a ground that I meant to fix, and forgot to on the '85. The one directly below the battery had rusted out, and was hanging by a thread. I cut off the connector, and put it to some better sheet metal in the same area. Hopefully that helps the alt out a bit. Didn't have a chance to test voltages yet though. I seem to have misplaced my multimeter at the moment.
December 31, 200916 yr I would say that something is going on other than just the alternator failing, and your alternator is gone again... How is your battery? I have seen alternators get fried because of a low charged battery. When the battery is low, the alternator tries to charge it. If it can't charge it for whatever reason, it just keeps on truckin' at full power, eventually wearing it's self out. So I would check/charge/replace your battery. If your battery is good, check all your grounds, corrosion causes resistance, and resistance can fry alternators. Truthfully, I would dump the stock alternator and get a bigger/better one. Nissan or GM, but I would take the time/effort to do it now, and then you won't have to worry about it. This is assuming it's JUST the alternator that went out and that there is no other underlying problem. If there is still a problem, replacing it with a Nissan/GM alternator isn't going to fix it, they will break down as well until the problem is fixed. This of course all costs money... that just happened to me today. the voltage was way north of the 18 mark just seconds later my stereo got fried and rite after the lil bit of smoke from the head unit the whole car went crazy. the needles were jumping around the red dash lites were on and the wipers were working by them selves. can any one point me as to wat else happened besides a fried alternator? o sorry to jack your thread...
December 31, 200916 yr that just happened to me today. the voltage was way north of the 18 mark just seconds later my stereo got fried and rite after the lil bit of smoke from the head unit the whole car went crazy. the needles were jumping around the red dash lites were on and the wipers were working by them selves. can any one point me as to wat else happened besides a fried alternator? o sorry to jack your thread... Check this other thread out, basically the same thing happened to this person. I have a good explanation there about what could have happened: http://www.ultimatesubaru.org/forum/showthread.php?t=106888 If you are still having issues/questions, start a new thread Good luck!
December 31, 200916 yr Author that just happened to me today. the voltage was way north of the 18 mark just seconds later my stereo got fried and rite after the lil bit of smoke from the head unit the whole car went crazy. the needles were jumping around the red dash lites were on and the wipers were working by them selves. can any one point me as to wat else happened besides a fried alternator? o sorry to jack your thread... See, now, I turned the radio off as soon as I noticed it. I just put a brand new Kenwood in it, and had no intention of replacing it this soon. I didn't have the wipers going all crazy on me though. And just for good measure, I bought some battery terminal cleaner, and some anti-corrosion stuff. Spent a few minutes cleaning the connections well, then hit it with the purple anti-corrosion to prevent any issues there. I was inspired to do this yesterday, when I went to start the car and it clicked without actually starting the first time. I figured I must have had a loose connection(or enough corrosion to matter), despite having just tightened down the battery terminals. Edited December 31, 200916 yr by Speedwagon
December 31, 200916 yr that just happened to me today. the voltage was way north of the 18 mark just seconds later my stereo got fried and rite after the lil bit of smoke from the head unit the whole car went crazy. the needles were jumping around the red dash lites were on and the wipers were working by them selves. can any one point me as to wat else happened besides a fried alternator? o sorry to jack your thread... The alternator was putting out a high AC ripple voltage due to bad diodes inside it and that is what ate your devices up.
December 31, 200916 yr The Bosch remans or replacements are quite poopie so don't go there. They seem to last two years less than the craptachi boat anchors. The last one I had failed and almost destroyed my battery, it was smoking and looked like a balloon:eek:! Battery still works though but I don't trust it.
December 31, 200916 yr The alternator was putting out a high AC ripple voltage due to bad diodes inside it and that is what ate your devices up. dammit . hey i put up my own thread on this. check it out.
December 31, 200916 yr dammit . hey i put up my own thread on this. check it out. Yes, I know. I was responding to your question about what happened. Hopefully the only thing that was damaged was the radio. Edited December 31, 200916 yr by Cougar
December 31, 200916 yr my Brat was doing the same thing right before i parked it for the winter. last trip to KC it was 18v then on way home it was not chargin but about 8 also, when get in car, to start, wipers would turn on, even though the switch was off. etc. my battery is no good at this point as well. and alternator(s) unknown. good luck report back, sure it will help me as i got the same. wierd.
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