Alternator Voltage.......

[LunchBox04V]

I was interested in finding out what you guys think about my system voltage on my car. Here is was happens......(note that all the voltage readings were given at driving RPM, that is around 2000-3000 RPM)

What it used to do......
At start, I know that the alt will be charging the battery for the start, and will run around 14.4v. After a while of driving (maybe a half hour) the voltage will stablize at around 14.1v (what I understand to be normal).

About 5 months ago......
The voltage started to vary around a lot. It would be running as described above. However, if I turned the car off and then started it again, it would drop to 13.6 or lower and would not come back up to 14.1v. On my trip to Minneapolis, it started at 14.1, and slowly dropped down to 12.9v! At that time, I turned the car off, and let it sit for about 30 seconds. After restart the voltage went back up to 13.9, and stayed there.

I think that the voltage regulator / alternator is going. In aviation, the system voltage stays where it is set up lets the power is set realy low (below 1000RPM). I went to the Subaru garage that I really trust, and they told me that it was FINE!!

What do you guys think?

[shazapple]

My brand new alternator only reads at 13.9 or so. The battery reads at 12 something when the car is off.

Have you been using the same multimeter for all your tests?

I wouldn't be too worried until the alternator dies. It can get you 60+km just on a fully charged battery. If you are really antsy about it then buy a new one just incase and keep a couple 10 and 12mm wrenches in the car :lol:

[LunchBox04V]

Yeah, it has been the same multimeter. I just thought that was a little strange, at least compared with my aviation knowledge. I will see how it works out!

[TRUBLU]

Perhaps it is time to start looking at your battery.....