Click for Abeking Click for Delta Click for Burger Click for Burger Click for Furuno

Rule 3700 bilge pump air lock

Discussion in 'Technical Discussion' started by enproep, Jan 5, 2015.

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

    enproep New Member

    Joined:
    Jun 7, 2011
    Messages:
    32
    Location:
    newport beach, ca
    Thanks all for all the great advice. Heading to the boat tomorrow to try out your suggestions. Thanks again, what a great forum!
    Bob
  2. Capt Ralph

    Capt Ralph Senior Member

    Joined:
    Sep 8, 2004
    Messages:
    12,647
    Location:
    Satsuma, FL
    Keep us up on what you find and how it was resolved.
    ,rc
  3. CaptGDunz

    CaptGDunz Member

    Joined:
    Mar 24, 2009
    Messages:
    60
    Location:
    Jersey Shore (North)
    This is a common issue with The rule 3700. A very technical yacht maintenance guru told me it has to do with the distance between the pump discharge and check valve. I apologize and do not remember the appropriate distance. Is some cases that may be difficult to remedy. How ever there is a simple fix for this that some might not agree with. Take the smallest drill bit in your drill index and drill a hole in the discharge of the pump that the hose is connected to. As soon as you do you will hear the pump gurgle. The pump will never air bound again. I have had problems with this on many Carvers, Marquis and just last week on a brand new Large Yacht. All Rule 3700 pumps. I've done it on pumps in sump boxes and bilge pumps. Works every time. And the tiny amount of water that leaks out while the pump is running is better than the sump box overflowing or the air bound pump eventually burning out from running constantly. On a brand new boat I had a Heat / Cool loop hose come off air A/C unit overnight. Over 400 gallons went in the bilge. The high water alarm woke me up. The brand new Rule 3700 was underwater running but not pumping. It could be a disaster on a boat unattended if a sea water hose let go.
    Last edited: Jan 27, 2015