Alternators were kinda after my time. I Like them but know little about them. My thirty-eight Ford has been converted to 12 volts. Driving home the other evening, I noticed my head light would dim for a second or two every now and then. Then I saw that my voltage gauge was only showing about 12 volts. It has always read around 14 volts up til now. When I start the car now the volt gauge shows 12 volts to start then in a second or two it jumps up to 14 then right back to 12, where it stays. Seems to me that maybe the voltage regular is failing. What do y'all think?
I believe the alternator should be putting out ~14.5, if it's not, you have a bad regulator or alternator (some regulators are internal, so replace alternator). If external regulator, try replacing that first (it's cheaper). You are likely showing ~12 because it's running/drawing power off the battery. Sounds to me like the fluctuation is the part failing, once it completely goes, it will drain your battery & leave you stranded. Good Luck! -jt
Sometimes if you can ID the alternator...then simply replace the internal regulator if that proves to be bad.
The Jalopy Journal
