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  1. #1

    I did some temperature testing today

    I recently purchased a digital temperature sensor. This thing is really cool. I have it Velcroed to the mirror where I can see it at speed.

    Today was a 81 degree day.

    The air temp at the bow right in front of my air intake was 86 to 88 degrees.

    At the rear of the boat right above the oil filter was about 125 degrees. This is where you would typically have a rear air intake.

    I have a rear air hole with about a foot of 2.5" hose in it that ends about 4" above the tunnel. The air temp in the center of the hose was right at 82 degrees so we know the vent is letting air into the hull. It is not letting hot air out of the hull.

    The water temp was 72. The sensor is waterproof. I will be using this setup for testing intercoolers.

    My ski has one of the front (3.5" ?) air inlet hoses removed and the other one has the length shortened.

    http://www.nbs-stl.com/RxpxTuning/DS...8Medium%29.JPG

    http://www.nbs-stl.com/RxpxTuning/DS...8Medium%29.JPG

    google or look on amazon for

    Bulerⓡ brand Digital temperature meter with remote temp sensor

    Andy
    Last edited by whittlebeast; 05-21-2015 at 09:52 PM.


  2. #2
    Quote Originally Posted by whittlebeast View Post
    I recently purchased a digital temperature sensor. This thing is really cool. I have it Velcroed to the mirror where I can see it at speed.

    Today was a 81 degree day.

    The air temp at the bow right in front of my air intake was 86 to 88 degrees.

    At the rear of the boat right above the oil filter was about 125 degrees. This is where you would typically have a rear air intake.

    I have a rear air hole with about a foot of 2.5" hose in it that ends about 4" above the tunnel. The air temp in the center of the hose was right at 82 degrees so we know the vent is letting air into the hull. It is not letting hot air out of the hull.

    The water temp was 72. The sensor is waterproof. I will be using this setup for testing intercoolers.

    My ski has one of the front (3.5" ?) air inlet hoses removed and the other one has the length shortened.

    http://www.nbs-stl.com/RxpxTuning/DS...8Medium%29.JPG

    http://www.nbs-stl.com/RxpxTuning/DS...8Medium%29.JPG

    google or look on amazon for

    Bulerⓡ brand Digital temperature meter with remote temp sensor

    Andy
    Andy, where do you have your 2.5 inch rear hole cut? Do you have it on one of the round areas under the seat at the rear? I'm very surprised its not letting hot air out! I've looked at those two locations (if its the one ones I'm thinking of) and thought it would be a way to get hot air out. I wonder if that hose is keeping the intercooler area any cooler?
    I'll have to have one of those temperature sensors.

  3. #3
    GGG's Avatar
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    heres the way ive always looked at it. The engine is a giant vacuum inside the ski. its gonna suck air from any direction it can. the only way your letting hot air out is if you have a scoop or blower forcing air in faster than the engine can take it or you have a vacuum on the back that is stronger than the motor.

  4. #4

  5. #5
    Quote Originally Posted by whittlebeast View Post
    Where did you get the hose fitting?

  6. #6
    They are off a very common seadoo. I do not recall what one. I paid like $6 on ebay.

  7. #7
    Seadoo part number 291002299

  8. #8
    Quote Originally Posted by whittlebeast View Post
    Seadoo part number 291002299
    Thanks

  9. #9
    Tiny's Avatar
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    Since your the engineer, could it be possible that it is not venting hte hot air but letting in cooler fresh air or is that just not possible????

    I also wonder if yours is not venting because of your hose sticking down to the bottom of the hull and not open like mine is????

    Hmmmmmmmmmm...........

  10. #10
    The end of the hose is wide open in the rear center of the hull. It ends above the tunnel and real near the front of the intercooler. Tubes like this and the flow thru them is totally a function of absolute air pressures.

    The motor is sucking huge amounts of air, so the interior of the hull is in a slight vacuum compared to the great out doors. This is where things get funny, behind the rider is a slight vacuum just from the air going around his body. Is that more of a vacuum than is in the hull from the motor, causing the rear vent to let out air? That is what the test was trying to prove.

    As a side note, every once in a wile, wile riding at speed, I would stick my hand back there to see if the air in the tube appeared to be hot. I never seemed to be any hotter than the great outdoors.

    Andy

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