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  1. #1

    Default 200HP blackmax overheating still!!!!!!!!!!

    Someone here can point me in the right direction. 1986 200HP black max Have changed waterpump,thermos, poppit and carrier but motor is still overheating.
    checked it in a barrel of cold water and tattletail is good and strong but gets so hot (in less then one minuet) that you cant put your hand under it been working on this motor for over a year now and this is the last problem to over come. Where do I go from here

  2. #2

    Angry Re: 200HP blackmax overheating still!!!!!!!!!!

    anyone have a idea what my next step is besides getting new motor

  3. #3
    Petty Officer 1st Class
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    Default Re: 200HP blackmax overheating still!!!!!!!!!!

    A easy thing to do wrong, is put the thermostat in the wrong direction.
    Maybe pull it out to see.
    Also, depending on what has happened to the motor, IE, was it out on the ground for a while? It could have some of the passages clogged. Not sure how yuo would check that.
    Did you rotate the impeller the correct way when you installed it? If backwards it may look like it is pumping enough, but not really.

    Just some thoughts, as no one else answered.

    I have a 1989 Black Max 200, for a couple months now, with no troubles.
    WHEW...

    Good Luck,

    Mike

  4. #4

    Default Re: 200HP blackmax overheating still!!!!!!!!!!

    Quote Originally Posted by mississippiriverrat View Post
    Someone here can point me in the right direction. 1986 200HP black max Have changed waterpump,thermos, poppit and carrier but motor is still overheating.
    checked it in a barrel of cold water and tattletail is good and strong but gets so hot (in less then one minuet) that you cant put your hand under it been working on this motor for over a year now and this is the last problem to over come. Where do I go from here
    I also have a 200 Black Max (1987). have changed waterpump, thermos, flushed with vinegar(to remove lake Alkali build-up), still overheats. What are poppit and carrier? tattletail fluxuates in strength, but, not overly hot like yours.

  5. #5
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    Default Re: 200HP blackmax overheating still!!!!!!!!!!

    RonnieBoy has been telling everyone to seal the water tube (w/blue siliclone) from the pump to the upper unit. I have never had that problem so can't help there. Good luck w/ your problem.
    I had my 89 200hp out yesterday for the 1st time in 3 1/2 months and it ran prefect, thank goodness, one never knows after they have set for awhile.

  6. #6

    Default Re: 200HP blackmax overheating still!!!!!!!!!!

    poppit valve or pressure relief valve on the left side of motor down low (looking from back) it lets more water flow through at higher RPMs. Thermos are in the right way will only fit one way have even tried running without them but still gets hot in less then a minuit at idol speed. Will pull lower unit and try the sealer to see if that helps any. Glad to here you guys are having good luck with your motors gives me hope for mine.

  7. #7
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    Default Re: 200HP blackmax overheating still!!!!!!!!!!

    water tube leak will let exaust gas that is under pressure , invade the cooling water stream and will actually raise the water pressure on a gauge, steam is the culprit , top seal is hard to replace, so just use blue silicone to make AIR PROOF, run down lake to see if water pressure jumps from say 7 to 10 pounds quickly, if you go from idle to full throtle, it should cool, mine did, wot my pressure was bout 24 pounds, at 5800 rpm. good luck ron
    me and forest , we be mates, 374vee

  8. #8
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    Default Re: 200HP blackmax overheating still!!!!!!!!!!

    24#'s is twice what my OEM says for my 1989 200hp. More like 12# is normal @WOT.

  9. #9
    Petty Officer 2nd Class
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    Default Re: 200HP blackmax overheating still!!!!!!!!!!

    the Ranger gauge hasnt ever lied, hahahah , i mean WOT, full trimed , wide open, with rooster tail, 24 pounds, no kidding, Mariner Mag II 1988 with 4 blade turbo 2+2 stainless prop. boat loaded or not bout 63 mph , doesnt matter. good luck ron
    me and forest , we be mates, 374vee

  10. #10
    Petty Officer 2nd Class 3car's Avatar
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    Default Re: 200HP blackmax overheating still!!!!!!!!!!

    Quote Originally Posted by mississippiriverrat View Post
    Someone here can point me in the right direction. 1986 200HP black max Have changed waterpump,thermos, poppit and carrier but motor is still overheating.
    checked it in a barrel of cold water and tattletail is good and strong but gets so hot (in less then one minuet) that you cant put your hand under it been working on this motor for over a year now and this is the last problem to over come. Where do I go from here
    Are you using a temp gauge to verify an overheating condition? I recently aquired an 87' 175 merc, and i suspected it was overheating too by the temp of the telltale waterstream. It was hot to the touch, but the water is coming from the back of the thermostats, so its gonna be. A check with a thermometer showed the water to only be between 135-140 degrees though.

  11. #11

    Default Re: 200HP blackmax overheating still!!!!!!!!!!

    Still no luck with over heat problem took boat out over weekend and will only run about 3 minunts intill the over heat alarm goes off checked tattle tale and was too hot to put you hand in ( got a blister to prove it ) still had good flow PSI running about 8-9 lbs, heads were also to hot to touch shut down and got towed back to dock. Will pull L/U off again and look at inlet tube to make sure it is not damanged, Will be headed down to help with flood cleanup in southeast Kansas for work for next 2 weeks will get apart when I get back and let everyone know what I find. Thanks again for all the help.

  12. #12
    Petty Officer 2nd Class
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    Default Re: 200HP blackmax overheating still!!!!!!!!!!

    still think its the water tube seals, should be lower pressure , mine would cool if i let it idle, or wot, no inbetween, good luck ron
    me and forest , we be mates, 374vee

  13. #13
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    Default Re: 200HP blackmax overheating still!!!!!!!!!!

    First check the popet valve seat, to be sure that it hasn't loosened and is moving out with the poppet valve.

    Then

    Powerhead base gasket or adaptor plate gasket
    either one fails and exhaust enters the cooling water passage, pressure raises on guage but water flow lessens and steam begins to form.

  14. #14
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    Default Re: 200HP blackmax overheating still!!!!!!!!!!

    think charlie b has it pegged, still say the exaust is gettin in the cooling water, wont work, does it cool when you idle tilted? ron
    me and forest , we be mates, 374vee

  15. #15

    Default Re: 200HP blackmax overheating still!!!!!!!!!!

    I had the same thing motor appeared to pump heaps of water but buzzer going off and when i put my hand on the heads it was very hot, started at the water pump, then the thermos, poppit valve head gaskets, base gasket and every time same crap.

    I was ready to get a new engine after so much frustration and money thrown at this thing. All done by a mechanic at my cost. I missed most of the summer skiing as every time I went out it lasted two minutes then back to mechanics.

    Anyway I saw a gearbox on ebay and won it for $45.00 ( thought after all the money I spent now $45 wouldn't matter). I put the box on and have never had a problem scince.

    Go figure. I don't know why but it works and have had about 100 hours of trouble free skiing ever scince

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