While running an errand last night I noticed the voltage gauge in my 1985 FJ60 was very low (around 8-10 volts depending on whether or not I had the lights, fan, or turn signals on). The truck had been sitting for about a week so I thought maybe something had been left on or one of the doors had been slightly ajar. I hoped it would charge back up while running but it did not. Today was the same story with very low voltage until I parked at home, at which point I could not start the car. Just a loud click and the starter slowly rotating momentarily, then nothing.
I ran the following tests with a multimeter:
- Battery reading while car was off: 12.6 volts
- Battery reading while running after being jumped (jumper cables still connected): 12.96 volts
- Battery reading while running after being jumped (jumper cables disconnected): 11.3 volts
My questions to you all...
1. Is it fair to assume this is a bad alternator that needs replacing? Battery is new and I don't have any new aftermarket electrical components. I did hook up the carb cooling fan ~2 months ago, but it shuts off right at 30 minutes so I don't think that is it.
2. Can I swap in an alternator from a normal parts store like autozone or o'reillys? I will hang on to my OEM and maybe get it rebuilt down the road, but I need to be driving by Monday. Do these options work?
3. Is the swap pretty straight forward? I'd prefer to do it myself and learn but my skills are limited. I swapped the starter, is it much more involved than that?
Thanks in advance!
I ran the following tests with a multimeter:
- Battery reading while car was off: 12.6 volts
- Battery reading while running after being jumped (jumper cables still connected): 12.96 volts
- Battery reading while running after being jumped (jumper cables disconnected): 11.3 volts
My questions to you all...
1. Is it fair to assume this is a bad alternator that needs replacing? Battery is new and I don't have any new aftermarket electrical components. I did hook up the carb cooling fan ~2 months ago, but it shuts off right at 30 minutes so I don't think that is it.
2. Can I swap in an alternator from a normal parts store like autozone or o'reillys? I will hang on to my OEM and maybe get it rebuilt down the road, but I need to be driving by Monday. Do these options work?
3. Is the swap pretty straight forward? I'd prefer to do it myself and learn but my skills are limited. I swapped the starter, is it much more involved than that?
Thanks in advance!
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