Regulator Problems "sudden overvoltage"

[sailheart]

This is my first attempt to post a question so bear with me if this shows up in the wrong place. I have a late model Atomic4 with the Motorola High Output alternator. The voltage meter has been indicating off scale jumps and the engine seems to load down so I shut it down quickly. I then restarted the engine and things seemed to settle down. With forward gear engaged I ran it up to 1500rpm and the same thing happened. I am not that familiar with alternator/regulator symptoms. Can anyone suggest an elimination process?

[msauntry]

Don't know about the Motorola specifically, but some alternators don't start charging until you spin them up to a certain rpm. Are your batteries worn down so far that the alternator is struggling to charge them?

Might just be time to rebuild the alternator.

[rigspelt]

No expert here, but I keep a voltmeter on the alternator output to detect VR failures (high volts) and take the alternator to an alternator shop if that happens.