Over the last year the alternator on my '87 22re has been acting up. First I had to replace the voltage regulator after a high voltage indication. A few months later I had to replace the rectifier after the post somehow snapped off. All parts came off my spare alternator. After a couple months of smooth operation it has now suddenly stopped charging. The brushes have lots of life left in them so I'm not sure what the problem could be. Time for a new alternator? Unfortunately there's no shop that bench tests alternators around here.

 

Here is a link with the diagnostic procedure once it is dissembled...

http://htftp.offroadsz.com/marinhake.../3generato.pdf

 

Thanks for posting that rustypigeon, I have my alternator out right now and I'd been wanting to do some checks on it.

jetpilot - how do you know the alternator suddenly stopped charging? Did your charge and brake lights come on or did you measure the battery voltage while running or what? Could be your charge fuse is blown, or a bad cable also. Maybe you can clip a meter lead right onto the bat post of the alternator, then check the voltage at the alternator while running to see if you get at least 14V.

 

The voltmeter dropped significantly while I was driving. I don't recall if the 2 red lights were on or not.

 

Schematic, explanation and suggested test points here