Alternator question

**milleniumz** · 01-08-2007, 12:11 PM

My battery (yellow top - four months old) was just replaced. It wouldn't take a charge. I got it exchanged and the new battery, original alternator and starter were tested and all were ok. I have just over 80k on my 2000z and have not added anything since 2002.

When I drive I notice my volts change from 14 to 13. When I test with volt meter, I get 14.1 at idle (600) and sometimes I get 13.9 at idle. What is the deal? Is it the voltage regulator on the alternator????

Should I just get a new alternator. I don't drive the car every day and when I want it, I don't want to wonder if I am going to be left on the side of the road.

Thanks.

**2001NBMZ28** · 01-08-2007, 12:26 PM

I have a red top and sometimes my voltage gauge will do that - but I drive mine every day. What voltage you getting on a meter with a cold start? I get 15.

**milleniumz** · 01-08-2007, 12:30 PM

I have not gotten more than 14.1.....weather isn't too cold here in Gville...

I will check it again in the morning. I will be up late watching the game tonight. I hope Ohio is ready for some fun.

**JEFF01Z** · 01-08-2007, 12:32 PM

That voltage is fine. There is nothing wrong with your alternator. The regulator will start off in the ~14v, then drop to ~13v range after it has been running for awhile. Might have had a defective battery. Is it going dead after you let it sit? If so it will sulffate the plates in the battery if it sets discharged for any period of time. A battery tender might be a good investment if you don't drive it very often. Even with that amount of miles I wouldn't think that the alternator is bad unless you have a big stereo system that is putting an excessive load on it.

**milleniumz** · 01-09-2007, 04:29 AM

I have PPI 4x125 amp, 10W3 JL sub, and 6.5 Focal Utopia's. But I installed back in 2002 and have never had a problem.

I will get a battery tender today, saw one at Pep Boys for about $50. It is just weird how we never pay attention to these things until it is too late. I never really paid attention to my volt meter, if I recall, I swear it was always just past the 13. Now it seems like it rides the 13 line!

My car has never stranded me on the road. I just want to make sure I am taking care of it as well. Thanks.

**JEFF01Z** · 01-09-2007, 07:33 AM

Mine normally hangs around 13 after it has ran for awhile too.
That amp will be fine on the stock electical system, just wanted to make sure.

Alternators won't last forever, they have brushes in them that wear. 80K miles would be a little early for them to wear out. Now if you had about 150k I would say it wouldn't hurt to take a look at them. Most of the time that is what goes wrong with them. The brushes in most alternators are fairly easy to change and sometimes that is all it takes to get it going again. It's a lot cheaper than replacing the whole thing.

**milleniumz** · 01-09-2007, 11:53 AM

I may crawl under the car this weekend. Do you know where to get the brushes or the part number. Do I need a soldering gun or special tools. Obvisouly, I would still have to remove from the car...

BTW, I did get the battery tender that my Dad uses on his Cessna to keep the battery ready to go. Since I don't drive the car often. This will help as well. I just want to get that piece of mind back, in time I guess.

Thanks Jeff.