sluggish take off

Discussion in 'Sterndrives' started by biggin, Jul 16, 2006.

  1. biggin
    Joined: Jul 2006
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    Location: missouri

    biggin Junior Member

    hello everyone I am havin some problems with my boats take off. When ever you give it full power it raises the bow real high and take a couple mins to plane out. We have put it time and checked all the plugs and wires and the fireing order and still nothing. it is an 89 22ft powerplay with a 350 4bbl in it, Does anyone have any suggestions or answers for me.

    thank you for lookin at im thrend.
     
  2. cirrus142
    Joined: Jul 2006
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    Location: Virginia

    cirrus142 New Member

    try trimming down some... ;)
     
  3. marshmat
    Joined: Apr 2005
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    Location: Ontario

    marshmat Senior Member

    Use of power trim: Before accelerating to plane, trim the drive fully down. Keep the drive down until you're on plane, then you can gradually trim out until the boat takes the proper running attitude. If it's a deep-V, you bring the trim in a bit before starting a turn, then put it back out when you're done turning.
    If proper use of the trim doesn't help, your boat is probably way too stern heavy. Move weight forward. Or maybe the trim pump is shot. If that doesn't help, trim tabs or a whale-tail could be in order.
    If anything were wrong with the engine, it would manifest as noise, vibration or sluggish response, not as a change in running angle.
     
  4. biggin
    Joined: Jul 2006
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    Location: missouri

    biggin Junior Member

    we have done that and nothing has happened could the pitch of the prop be a factor or no cause mine is a 21in pitch sould we go a size down or up??
     
  5. marshmat
    Joined: Apr 2005
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    Location: Ontario

    marshmat Senior Member

    "21in pitch" doesn't say much... to know what that prop is, you also need diameter, blade count, blade type... ie. " 14.5x21 three-blade stainless with a slight rake ". If the prop is too steep, your engine RPM would be lower than spec at full speed; if the prop's too shallow, the RPM will be too high. You can of course size a prop for better acceleration at the cost of lower top end; however, a high-performance boat like your Powerplay would typically come from the factory with a properly sized prop.
    I still think there's a trim problem involved. Have someone work the trim switch while you stand on the swim platform (ENGINE OFF!). I presume you have a Bravo 1 as do most boats like this? Make sure the trim cylinders both extend and retract smoothly through their full range, with no weird noises. Then move away from the boat (ie stand on the dock) and watch it move up and down with the engine in gear. Any hesitation in the trim motion, or odd sounds, would indicate a problem with either the trim pump or cylinders.
     
  6. biggin
    Joined: Jul 2006
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    Location: missouri

    biggin Junior Member

    my lower unit is a alph1 anf my diameter is a 15.25 with 3 bladeswe will try the my test again and see if anything happens.
     
  7. biggin
    Joined: Jul 2006
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    Location: missouri

    biggin Junior Member

    would the prop being damaged somewhat cause bad take off and vibration?
    could the carb be bad it is a 4bbl quad jet carb?
     
  8. Frosty

    Frosty Previous Member

    Dont you believe Marshmat then? Have you seen how many reputation points he has and how many posts. His advice is correct if you need another opinion.
    To lift the bow of a 22foot boat needs power, you obviously have that to be able to do that. Marshmat is obviously familiar with this boat. You are not transmitting the power in the correct plane ,ie there would appear to be some thing wrong with the trim of the leg that pushes the boat forward. If it is not in its lowest position for 'take off' it will lift the bow high in the air and take a good few seconds to get over the hump before it comes down. This is your problem yes? Check the oil level in the trim pump and check for full movement of the leg.
    The cavitation plate ( the big plate thing above the propellor) should be in line with the boat at lowest trim, even more infact as if the prop was going under the boat. If neccessary put a piece of wood accross it to see if it is in line with the hull bottom.But you should be able to tell from the movement of the hydraulic rams.
     
  9. biggin
    Joined: Jul 2006
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    Location: missouri

    biggin Junior Member

    marshmat i was wounderin if the lower unit is supposed to move from side to side but its not moving the sterring wheel when you move.
     

  10. Frosty

    Frosty Previous Member

    Biggin your questions are frightening. Sell the boat and buy a bicycle before you kill some one.
     
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