• Creator
    Topic
  • #33726

    Frank Thweatt Jr
    Participant
    Vessel Name: STEELREELN
    Engines: QSB 5.9
    Location: Apalachicola florida
    Country: USA

    Qsb 5.9 – battery voltage would rise up to 17 volts at high rpm then drop back to 14 at idle rpm , could it be voltage regulator and it showing on both engine with separate gauges so thinking its not alternator, Looking for help for a place to start looking for problem. Thanks

Viewing 2 replies - 1 through 2 (of 2 total)
  • Author
    Replies
  • #33728

    Tony Athens
    Moderator
    Vessel Name: Local Banks
    Engines: QSB 6.7 550 HP
    Location: Oxnard, CA
    Country: USA

    The symptom you describe would typically be related to the internal voltage regulator failing, inside the alternator. Simple to exchange alternators of take it off and have it repaired. Or do both, then you have a spare.

    But do follow Phil’s lead regardless.. Very important.

    Tony

    #33727

    Philip
    Participant
    Vessel Name: 2007 35’ Cabo ‘FUGA’
    Engines: Cummins QSC8.3-540’s
    Location: Long Beach, CA

    Have you verified voltages at back of alternator and at battery with a hand held meter to confirm?

    I’d start at the battery terminal and clean every connection between the battery and alternator with WD40 and emery cloth 100% shinny clean and then make sure all is tight.

    Sounds like a dirty or bad connection. You often look at a terminal and think it’s clean only to find it dirty upon disassembly.

    Phil

Viewing 2 replies - 1 through 2 (of 2 total)

You must be logged in to reply to this topic.