Click for Westport Click for Burger Click for CL Yachts Click for Northern Lights Click for Delta

Cabo 35’ water intrusion

Discussion in 'Technical Discussion' started by Cabo35’RI, Sep 17, 2026.

You need to be registered and signed in to view this content.
  1. Cabo35’RI, Sep 17, 2026
    #1
    Cabo35’RI

    Cabo35’RI New Member

    Joined:
    Oct 16, 2021
    Messages:
    3
    Location:
    Watch Hill RI
    I have 2002 35’ Cabo Express. Having sea water intrusion only when underway. Nothing at the slip. New dripless shaft seals, new rudder shaft seals. Bellows on mufflers not leaking. Thru hulls & seacocks appear ok. No intrusion in the engine room or forward bilge area. Appears to be coming from aft area and will migrate to engine room when coming off plane. On a typical 4-6 outing I get about 3-4 gallons. Had my diesel mechanic on board for 2 hours underway and we are stumped. Help!!!!
  2. MBY, Sep 17, 2026
    #2
    MBY

    MBY Senior Member

    Joined:
    Dec 17, 2009
    Messages:
    122
    Location:
    Newport Beach, CA
    Pull the fishboxes and go do another run. Could be a leak on one of the bellows perhaps
    Capt Ralph likes this.
  3. Capt Ralph, Sep 17, 2026
    #3
    Capt Ralph

    Capt Ralph Senior Member

    Joined:
    Sep 8, 2004
    Messages:
    14,538
    Location:
    Satsuma, FL
    In another site I was trying to offer;
    Water coming the engine room vents and not draining out properly.

    I think MBY has a better idea than mine.
    Last edited: Sep 17, 2026
  4. Cabo35’RI, Sep 18, 2026 at 9:56 AM
    #4
    Cabo35’RI

    Cabo35’RI New Member

    Joined:
    Oct 16, 2021
    Messages:
    3
    Location:
    Watch Hill RI
    MBY & Capt Ralph… thanks!

    I did pull both fish boxes and ran her. There was a very small leak on the port side bellows that enters the muffler. Was about 1 drip every 30 seconds and not sure that would equate to 3-4 gallons for about 6 hours of running. Unfortunately didn’t have a 5/16 Allen wrench on board but did tighten it back at the dock.
    Water seems to be accumulating in the aft compartment when on half plane.
  5. MBY, Sep 18, 2026 at 10:24 AM
    #5
    MBY

    MBY Senior Member

    Joined:
    Dec 17, 2009
    Messages:
    122
    Location:
    Newport Beach, CA
    Id have to go back and ask the guys that would remember but there could be a chance that you have a leak in the engine room, water is getting under the engine room liner and when you start running it flows aft into the aft bilge. At rest you wouldn't notice anything in the engine room but underway you would. I can't remember if the bottom of the engine room liner was sealed aft I believe it was but again its been 20 years since I saw a 35 before the tanks went in
  6. Cabo35’RI, Sep 20, 2026 at 1:56 PM
    #6
    Cabo35’RI

    Cabo35’RI New Member

    Joined:
    Oct 16, 2021
    Messages:
    3
    Location:
    Watch Hill RI
    MBY.....thanks for the response. There are what I call containment wells (perhaps for oil spills?) under both CAT 3126B engines. We ran the boat hard and fully inspected both engines and wells while underway. No water in engine room. Water seems to emanate somewhere between the aft bilge area then forward to the engine room via a small drain hole in the bottom of the generator bulkhead. Hole was really plugged up before we cleaned it. A rod & cloth was used to clean out the hole and the rod eventually hit another bulkhead (or the fuel tank??).

    To your knowledge, is there a void between the hull and the bottom of the fuel tank? Just forward of the transom there is a cross-hatch platform with a void that drains forward (somehwere?) Any aft water wants to end up in the engine room low point where midship bilge pump is.

    As I may have mentioned, the only water noticed was about 2 drips a minute from the port side exhaust intake (to muffler).

    Let me know if you have any suggestions. Really at a loss here. Thanks!!