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  1. #1
    skigolfnut's Avatar
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    Water routing for pro 785

    With all the different drawings I have printed from the water routing thread in the performance section I am still a little bit confused?

    We have a very steep ramp where we launch at, and we have to really throttle up the trailer to get it hooked up, and sometimes even help push the vehicle up with the ski,
    I have a bone stock 1997 and a unlimited class 1998,
    For the 1997 the best routing is the Randy Watcon drawing?
    And I tap the water manifold for the line marked "C"?
    And put in a Jetworks valve?

    For the 1998 limited I have cooling hoses coming off the head out the rear of the ski,
    Does that cure the problem all together for the 1998?
    see attached picture,
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  2. #2
    thester71's Avatar
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    I would follow the watcon routing on both.

  3. #3
    Click avatar for tech links/info, donation request K447's Avatar
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    The issue with the Pro 785 was the water that is injected INSIDE the exhaust system could flow back into the engine when the engine was shut down and the hull nose was lifted up (as is is on a launch ramp trailer).

    The cooling water from the engine water jackets that simply exits through the rear or side hull fittings isn't the problem.

    The water injected into the exhaust stream in the early configuration would accumulate in the exhaust collector box in the front of the hull, especially when the engine was running at low RPM for any length of time, such as a idling through a long low speed or no wake zone back to the trailer. When the nose was tipped upwards during trailer loading and the engine shut off, that accumulated water would flow downhill and run right into the engine through the exhaust ports.

    If you could zoom right up to the trailer and load immediately, then there wasn't a problem. That is why the racer's often didn't have a problem. They could zoom back in after a race, kill the engine, and load onto the trailer or beach cart.

    The revised water routing may change the water flow pattern for the engine, but the important aspect is how the water feed for the exhaust pipes was changed.

    The idea was to greatly reduce the amount of water present in the collector box, especially during idle and low RPM. The Jetworks valve is a big part of that, since it diminishes water flow at low RPM.

    At high throttle levels, there isn't a problem, since the powerful exhaust flow simply blows all the injected water right through the exhaust system.

  4. #4
    skigolfnut's Avatar
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    Many thanks, were do you get the jetworks valve?
    I am looking at all the threads on the subject and I see that the Randy Watcon drawing seems to be the way to go, no matter what year,
    Am I reading it correctly to take all the restrictors out and use the listed hose size instead?
    and take out the thermostat correct?

  5. #5
    The water routing on both of your skis has been changed and should be fine. I never had any issues with either of them on a ramp, tote or otherwise.

  6. #6
    Click avatar for tech links/info, donation request K447's Avatar
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    Quote Originally Posted by skigolfnut View Post
    ...where do you get the jetworks valve?
    ...
    From Jetworks

  7. #7
    Kerminator's Avatar
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    Quote Originally Posted by skigolfnut View Post
    Many thanks, were do you get the jetworks valve?
    I am looking at all the threads on the subject and I see that the Randy Watcon drawing seems to be the way to go, no matter what year,
    Am I reading it correctly to take all the restrictors out and use the listed hose size instead?
    and take out the thermostat correct?
    I am wondering the same thing with my PRo, do you take out the thermostat?

  8. #8
    She likes the bike. But the ski gets her wet!!!! xlint89's Avatar
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    Quote Originally Posted by Kerminator View Post
    I am wondering the same thing with my PRo, do you take out the thermostat?
    Most people do.

  9. #9
    Kerminator's Avatar
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    Quote Originally Posted by xlint89 View Post
    Most people do.
    What is the reason behind this? are the advantages and disadvantages of doing this. The thermostat is located in the head correct? Sorry Im a newbie and just trying to get my new ski in shape before summer. Thanks!

  10. #10
    She likes the bike. But the ski gets her wet!!!! xlint89's Avatar
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    Thermostat is only meant to help speed up proper warm up of the engine. Or if you're going to ride in really cold water. Say 50* or less temps.

    The advantage is, if the thermostat gets stuck you'll overheat. If it's removed, that'll never happen.

    The only disadvantage is you need to properly warm your ski up before running WOT. Only needs to be ran for around 5 mins before going WOT. (most no wake zones takes care of this)

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