A "new" alternater can be blown out by jumping the car incorrectly or shorting the output to ground even for a second. The way I check for a loose belt is to try to turn the pulley on the alternater by the fan behind the pulley. It should be hard to turn and it should move the belt. Too tight and you will blow the bearings in the alternater and wear out the belt. I have seen where the pulleys are worn and the belt is touching the bottom of the pulley. It should only touch the sides. You can purchase a gauge to check for a worn pulley. The wrong belt that isn't the right angle will slip under heat and load. You need to have the alternater bench tested and if needed they are repairable or rebuildable at much less than replacement cost. One blown diode will reduce the output significantly and impose an AC voltage on the system which will blow light bulbs and destroy the battery. Most places will put a charging system analyzer on the car for free (like Sears) and will pinpoint the problem for you. David Teitelbaum vin 10757 --- In dmcnews@xxxx, Soma576@xxxx wrote: > Hey all, > > to recap, my problem is this: > > for the last month or so, every now and then my battery light would flicker > for a few seconds and then go out again, usually accompanied by a brief drop > in voltage on my gauge, to about 10 volts or so, then it would go back up on > it's own. this would especially happen during high RPM's, but seemed to also > be somewhat random. then this last week, things got ugly. on the way home > from work ( a 10 mile drive) my battery light was constantly flickering and > my voltage was down around 8-10 for almost the entire drive home. i have a > 130 amp alternator installed by the previous owner a little over a year ago, > with new belts this spring by myself. > > anyway, i posted earlier this week on what i should inspect. i have so far > inspected my battery connections - they are tight. i checked the front > ground strap - i cleaned it and reattached it. i checked the rear trailing > arm ground strap - it is still epoxied over so i decided to leave well enough > alone. i tightened my belt (it had a little slack in it) and started the > car. it's still only running at 8-10 volts. > > now what do i do? do i have to bite the bullet and order a new alternator? > it's hard to believe that this one hardly lasted longer than a year!! > > which DMC vendor offered the 130-amp alternator? i checked through a few > sites tonight but no one had this alternator listed. what is the track > record of it?? should i reduce down to the 105-amp alternator, or should i > get the much cheaper 150 amp alternator? and is the voltage regulator > serviceable without rebuilding the entire alternator? > > any advice would be greatly appreciated about now because this is quite a > show-stopper! > > Andy