Click for Mulder Click for Delta Click for Perko Click for Westport Click for Cross

Bow Thruster overhaul/refit

Discussion in 'Technical Discussion' started by cdg, Apr 6, 2013.

You need to be registered and signed in to view this content.
  1. cdg, Apr 6, 2013
    #1
    cdg

    cdg Member

    Joined:
    May 15, 2009
    Messages:
    41
    Location:
    wellington, new zealand
    My Wesmar DPC-50 bow thruster isnt working. Seems the shaft doesnt want to engage under load. Its only 12 years old; and given we're mostly at sea, isnt used often. Wesmar said 'we no longer support that model - which ir remarkable - so no spares, and please buy a new one! So can someone advise: a) a thread for overhaul/refit info, or b) where I can get spare shafts?

    Thanks in advance.
    C
  2. Capt Ralph, Apr 6, 2013
    #2
    Capt Ralph

    Capt Ralph Senior Member

    Joined:
    Sep 8, 2004
    Messages:
    13,439
    Location:
    Satsuma, FL
    Where does "the shaft doesn't want to engage under load" happen? Pinion gear? motor coupling? wheel hub or clutch? Motor rolls over when engaged? Breaker triping ?(Assuming it's electric). What did the oil look like when last inspected? OR any last inspection results? Was it inspected on last haul???
    Your kinda of thin in your failure description and history.
    I have found that even the most ugly failures are usually something simple.

    Give us a little and maybe we can help you fix it.
  3. Capt J, Apr 6, 2013
    #3
    Capt J

    Capt J Senior Member

    Joined:
    Jul 11, 2005
    Messages:
    14,530
    Location:
    Fort Lauderdale
    Have you checked to make sure the propellor is not spinning the hub? This is by far the largest problem in bow thrusters.
    I agree that you're opinion is very vague
  4. NYCAP123, Apr 7, 2013
    #4
    NYCAP123

    NYCAP123 Senior Member

    Joined:
    Mar 14, 2008
    Messages:
    11,208
    Location:
    Long Island, NY
    It's not unusual for a 12 y.o. anything to be no longer manufactured and parts not available today. I'd check the prop, and if beyond that get a new thruster. If the shaft is indeed bad, what else is worn out and ready to go? If you insist on trying to repair, then it may be time for a trip to a bone yard.
  5. Fishtigua, Apr 7, 2013
    #5
    Fishtigua

    Fishtigua Senior Member

    Joined:
    Jul 20, 2007
    Messages:
    2,935
    Location:
    Guernsey/Antigua
    Have a look at the plate on the motor. Wesmar used to buy them in and the brushes often go. Motor brushes can be bought to fit most any one of them.
  6. cdg, Apr 7, 2013
    #6
    cdg

    cdg Member

    Joined:
    May 15, 2009
    Messages:
    41
    Location:
    wellington, new zealand
    Thanks guys - will get some more info and post back. My apologies for apparent vagueness.
  7. cdg, Apr 8, 2013
    #7
    cdg

    cdg Member

    Joined:
    May 15, 2009
    Messages:
    41
    Location:
    wellington, new zealand
    Thanks guys - love it!
    Apologies for the lack of info - wasnt intending to be vague. My engineer reported:

    I barred the shaft and couldn't spin the props. I then disconnected the motor( hydraulic) from the gearbox. I ran the motor it sounded fine, and turned with force. Had a tech down to look at motor, he agreed motor sound fine and didin't it needed to go the workshop. I then had the props spun and watched the shaft from gearbox to motor spin while disconnected. It turns but not consistantly leading me to believe that some gears have spat teeth. I got a mate coming down tomorrow to spin the props while i hold the shaft and confirm that's the problem.

    So, hope that provides the info you need? Many thanks again in advance. cheers
  8. Navatech, Apr 8, 2013
    #8
    Navatech

    Navatech New Member

    Joined:
    Mar 27, 2013
    Messages:
    89
    Location:
    Hollywood, FL
    OK, so clearly the motor is OK.

    Inconsistent spinning of the props would lead to inconsistent turning of the geas. Get a couple of walkie-talkies to make sure that you know when the props are being spun.

    If you still see inconsistent turning of the gears it would tend to indicate damaged gears. Hopefully you can source these and rebuild the thruster.
  9. Seaclusion, Apr 8, 2013
    #9
    Seaclusion

    Seaclusion New Member

    Joined:
    Sep 24, 2008
    Messages:
    16
    Location:
    PNW
    If it is a hydraulic motor, then to engage the thruster there is a rubber donut on the shaft attached with set-screws. If the set-screws back off, then the donut will not engage. Been there, done that with a WESMAR. You may need a new rubber donut, as these do wear out.

    Doug Crim
    Seaclusion