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  1. #1

    pro 785 problems

    bought pro 785 new in 1997. after 15 hours motor sezied.dealer said engine getting no oil warranty motor. fresh rebuild i dont ride it much maybe 1 every year. now it has 30 hours motor felt like it seized again. did compression test 145,110,145. are these boats garbage or are they just super unreliable.i dont race or even ride flat out. should i disconnect oil injection and premix.. when boat runs very fast,but 2 motors in 30 hour span. maybe dealer didnt bleed oil lines. to scared to use this boat anymore.jetting looks good plugs nice and brouwn. please someone help !!!!!!!!!!!!!!!!!


  2. #2

    Join Date
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    There GREAT boats after all these years i would go premix and not have to worry about it.

  3. #3

    pro 785

    do they have a problem with the oil injection... is this a common thing ... what should the compression be ... how do you make it a premix machine...

  4. #4

    Join Date
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    the oil pumps where and are very reliable ,your compression should be 125-150 tops .for blocking off the oil injection you can buy the block off plate from Randy @ Watcon www.watcon.com
    you'll just need to remove the pump and all the lines and oil tank and thats it, also tie up the float so it still reeds full or install a resistor in the wiring to fool the cdi.

  5. #5

    pro 785

    are the middle cylnder compression suppose to be less than others.. i read that you are suppose to bleed oil injection mine looks like there could be air bubbles in the oil lines.. i would prefer to keep oil injection but after 2 motors just dont trust it ... how much oil does your 785 use.mine is a 1/4 tank of oil to one tank of fuel...

  6. #6
    SPEED KILLS, BUT YOU GET THERE QUICKER Keddano's Avatar
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    Jul 2007
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    All cyls should be within 10% of each other,so yes the middle is low. You may have started to burn it down.I would also do a complete fuel rebuild,including carbs.A ski that gets little use is worst then one used alot.Fuel sits and evapolrates and makes gunk in them and can plug jets causing a lean condition that will burn pistons.

  7. #7

    pro 785

    when i remove the head how do i tell if it ran to lean or the oil injection wasnt working.... how much oil does yours use mine uses 1/4 tank to 1 tank of fuel

  8. #8
    SPEED KILLS, BUT YOU GET THERE QUICKER Keddano's Avatar
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    The top of the piston will be burnt if lean,normally lack of oil will leave scratches in the cyl bore.Do a search for "Piston Wash" to see how a well tuned carb. will leave colored combustion marks on the piston.

  9. #9
    Remove all 3 heads and post up a pic of what you find.

  10. #10

    pro 785

    now i final feel like im getting some were. i will take pictures of pistons and cylinders tommorrow and post. thank you guys very much

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