Click for Seacoast Click for Lurssen Click for Westport Click for Cheoy Lee Click for United

My 230v generator has decided it is 400v

Discussion in 'Generators' started by HaveADay, Jul 30, 2016.

You need to be registered and signed in to view this content.
  1. HaveADay

    HaveADay Member

    Joined:
    Apr 22, 2015
    Messages:
    34
    Location:
    Chicago, IL
    Hello,

    Last sunday my 2003 Kohler 23eoz with about 1100 hours on it decided it was no longer a 230v generator and instead a 400v generator. It was putting out 199v per leg. This unfortunately resulted in frying two of my air conditioning units and two battery chargers.

    I called the yard I use for service who dispatched a technician and in working with Kohler decided the generator needed a new rectifier. I´m not 100 % clear on this becuase when I looked at the parts manual for my generator I wasn´t able to find a rectifier listed. The board they replaced is a circular board with six diodes and what looks like a VOR that goes at the back end of the windings. The board cost about $230 and my pessimism quickly kicked in. Rarely does a $230 part fix anything I break (or so I feel.) So today the part was replaced and low and behold the generator still produces a stead 400v. Now they are jumping to thinking the windings are the problem and it could need a new stator.

    I´m wondering if others have come across this and might have any ideas about what would cause the generator to produce a seemingly stable 400v. I"m wondering if the governor could have failed. I wouldn´t think the voltage regulator would be in play because I wouldn´t expect a healthy generator to produce 400v at any time.

    Thoughts? Ideas? Random tests I can try? Anyone know of a good stepdown transformer from 400v to 230? Kidding....

    I´m a little punch drunk from a day of replacing the failed components in my AC system. That is now all back together but I´d like to get the generator straightened out before I fry another bunch of equipment.

    Thanks!

    Ben
  2. bobhorn

    bobhorn Member

    Joined:
    Mar 3, 2014
    Messages:
    165
    Location:
    Kemah, TX
    The six diodes are the rectifier. Can't help beyond that.
  3. Capt Ralph

    Capt Ralph Senior Member

    Joined:
    Sep 8, 2004
    Messages:
    8,252
    Location:
    Satsuma, FL
    Got to be a run-away voltage regulator.

    There are a few test points pointed out in the service manual.
    If your not familiar with working on running gen-sets, Time to find a proper tech.
    You can do more than kink your hair.
  4. dennismc

    dennismc Senior Member

    Joined:
    Jan 29, 2009
    Messages:
    1,137
    Location:
    Vancouver BC
    Sounds like a vr, had the same on my Onan when in Mexico, can be tested and verified
  5. HaveADay

    HaveADay Member

    Joined:
    Apr 22, 2015
    Messages:
    34
    Location:
    Chicago, IL
    Indeed it was the VR. Replaced and back to 230v.

    Ben
  6. Capt J

    Capt J Senior Member

    Joined:
    Jul 11, 2005
    Messages:
    12,067
    Location:
    Fort Lauderdale
    Good news, it sucks that you had so much equipment fry because of it.

    I've replaced more 6-12 batteries at a shot because of a battery charger going bad, more times than I'd like to count.