transom tunnel troubles

Discussion in 'All Things Boats & Boating' started by texas nitro, May 31, 2005.

  1. texas nitro
    Joined: May 2005
    Posts: 13
    Likes: 0, Points: 0, Legacy Rep: 10
    Location: houston

    texas nitro Junior Member

    can anyone help??
    2005 nitro bay boat transom tunnel 8 inch taking on water between transome and engine bracket and will not plane properly :confused:
     
  2. marshmat
    Joined: Apr 2005
    Posts: 4,127
    Likes: 149, Points: 63, Legacy Rep: 2043
    Location: Ontario

    marshmat Senior Member

    Taking on water between transom and bracket? You may have some deteriorating seals; then again, your bracket could be cracking your transom laminate. Bracket will ahve to come off and transom needs a full inspection.

    Not planing? Could be because of the water sloshing around the bilge; also, if your bracket or transom has taken damage your motor will no longer be at the right height or trim, and could be flexing the hull when gunned.

    You'll probably have to pull the engine and bracket and thoroughly measure and check everything to get a better diagnosis.
     
  3. texas nitro
    Joined: May 2005
    Posts: 13
    Likes: 0, Points: 0, Legacy Rep: 10
    Location: houston

    texas nitro Junior Member

    Thanks, But this is a brand new boat, It Has been doing this since i got it.
    I have taken it back to the dealer 4 times, they 1st changed motor said it had a pontoon motor with big foot lower end.
    installed the correct mercury 60 hp 4 stroke, 2nd trip raised engine 1 hole and took out trim pin, 3 rd tip raised engine 1 hole, 4th trip same.
    let me see if i can explain, the water is riding up the back of the boat in between the engine bracket and transome then coming into the boat at the top of the engine bracket where it makes it hook to the inside of the boat.

    I was Wondering if the engine was running too deep causing the bottom of the bracket to dig in?
    Is There anyway too visually tell where the motor should sat trimed all the way down in conjunction to the botom of the boat?

    The Plaining Problem Accualy got worse when i installed a tiger shark hydrofoil, it takes about 15 seconds to plain, and even that has to be worked.

    would a jackplate help?
     
  4. marshmat
    Joined: Apr 2005
    Posts: 4,127
    Likes: 149, Points: 63, Legacy Rep: 2043
    Location: Ontario

    marshmat Senior Member

    Trimmed level, the motor's antiventilation plate should be between level and 1" below the keel on most boats; try to get the motor height about here.

    Some photos of your installation would really help with the water issue. This is a very dangerous condition if you're getting substantial amounts of water coming in. From your description it's hard to tell if you're talking about a motor that's mounted on an external bracket, or a motor with an integral bracket that's mounted on the transom. Is the water coming over the top of the transom? As for the planing problem: does it plough? is there excessive bowrise? does it stuff the bow down too soon?

    I'd avoid spending money on new gadgets (jackplate etc) until you have the problem fixed.
     
  5. texas nitro
    Joined: May 2005
    Posts: 13
    Likes: 0, Points: 0, Legacy Rep: 10
    Location: houston

    texas nitro Junior Member

    It is a motor with an integral bracket that's mounted on the transom.
    And yes it is coming over top of transomwhen coming off plane.
    It originally came in will trying to get on plane around 3000 rpms and come in alot,like someone stuck a hose pipe between the transome and motor shooting straight up, now it only comes in while coming of plane for about 4 second.

    planing, it plows through water trimed all the way down and will not pick up enough speed to get on top, you have to tim up while planing up or you stay plowing water all the way down at around 4000 rpms WOT
     
  6. Corpus Skipper
    Joined: Oct 2003
    Posts: 606
    Likes: 8, Points: 0, Legacy Rep: 173
    Location: Corpus Christi TX

    Corpus Skipper Hopeless Boataholic

    You should only have the engine trimmed all the way down to get out of the hole, and trim up while coming on plane. This is how it's supposed to work. Trimming up will get the bow out of the water, give you a better ride, and more speed. Trim up untill she starts to porpoise or ventilate, then trim down just a little and you'll be in the "sweet spot".
    You should pick up RPM as you trim up, but it sounds like you're over propped, you should get 5500 RPM or more, check your owner's manual.
     
  7. marshmat
    Joined: Apr 2005
    Posts: 4,127
    Likes: 149, Points: 63, Legacy Rep: 2043
    Location: Ontario

    marshmat Senior Member

    Water coming over the transom is often an issue with low-profile boats, especially if they aren't trimmed right. Sounds to me like you really should have a motor well, but apparently don't... Try Craig's advice about trim settings; this should get it working. If not, your rig is probably set up totally wrong (wrong height, wrong prop) and should be adjusted professionally according to the designer's drawings.

    Tunnels of any sort, especially single-engine ones, are very sensitive to trim, height and load conditions.
     

  8. marshmat
    Joined: Apr 2005
    Posts: 4,127
    Likes: 149, Points: 63, Legacy Rep: 2043
    Location: Ontario

    marshmat Senior Member

Loading...
Similar Threads
  1. Jfrost
    Replies:
    3
    Views:
    996
Forum posts represent the experience, opinion, and view of individual users. Boat Design Net does not necessarily endorse nor share the view of each individual post.
When making potentially dangerous or financial decisions, always employ and consult appropriate professionals. Your circumstances or experience may be different.