Repeated alternator failure
I have a 1988 Ford Econoline chasis Class C Motorhome. My wife was recently returning home in our motorhome and had all of the gauges fail, the seatbelt light came on and the engine shut off. She ha...
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Working night shift last night, thanks for all the great advice while I slept this morning!
I rechecked everything this afternoon when I got up. Alternator post at the isolator was receiving ~ 28 volts, house battery post at the isolator was receiving 28 volts but chassis post at the isolator as well as the battery terminals themselves were at 12.05 volts. Because the reading at the battery and the chassis battery post on the isolator were identical, I assumed that the continuity of the wire was intact.
The alternator was working, albeit a little too well at 28 volts! I moved the chassis battery cable to join with the alternator cable on the alternator post in order to bypass the isolator (and crossed my fingers that I wasn't going to fry my battery with 28 volts!)....
13.7 volts!!!!!!!!! I took Ol' Reggie for a bit of a drive, and measured 14.2 volts at the battery terminals when I got back. All three posts on the isolator are now measuring 14.2 volts as well. Honestly, that part does confuse me a bit - why was there no charge coming through the chassis battery post before, but no with no wire hooked up to it, it seems to be ok? Maybe too much resistance with the battery hooked up?
Anyhow, the mystery seems to be solved, just wondering if my alternator was ever bad in the first place. Hopefully, this post will help others trouble shoot a possible isolator failure rather than shelling out $$$ to replace alternators!
I rechecked everything this afternoon when I got up. Alternator post at the isolator was receiving ~ 28 volts, house battery post at the isolator was receiving 28 volts but chassis post at the isolator as well as the battery terminals themselves were at 12.05 volts. Because the reading at the battery and the chassis battery post on the isolator were identical, I assumed that the continuity of the wire was intact.
The alternator was working, albeit a little too well at 28 volts! I moved the chassis battery cable to join with the alternator cable on the alternator post in order to bypass the isolator (and crossed my fingers that I wasn't going to fry my battery with 28 volts!)....
13.7 volts!!!!!!!!! I took Ol' Reggie for a bit of a drive, and measured 14.2 volts at the battery terminals when I got back. All three posts on the isolator are now measuring 14.2 volts as well. Honestly, that part does confuse me a bit - why was there no charge coming through the chassis battery post before, but no with no wire hooked up to it, it seems to be ok? Maybe too much resistance with the battery hooked up?
Anyhow, the mystery seems to be solved, just wondering if my alternator was ever bad in the first place. Hopefully, this post will help others trouble shoot a possible isolator failure rather than shelling out $$$ to replace alternators!
