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  1. #1

    Pro 785 Performance Issue

    I need some help diagnosing an issue. I have a 97 Pro 785 that is stock and a 98 that is has limited class race mods. This weekend, the 98 was running 7850-7900 rpm in smooth water with morning temps around 80. The 97 couldn't get past 7000 and felt sluggish. No bogs or anything, just no rpm. I'm thinking it has to be either a cracked pipe or something with the exhaust vavles.

    I ran it on the trailer at the ramp and didn't see any water coming out of the pipes. The exhaust valves appear to be working properly. The carbs look fine also. It ran fine the last time out, so I'm not sure what has happened.


  2. #2
    Watcon's Avatar
    Join Date
    Oct 2005
    Seattle WA

    785 issues.

    Leak test all the pipes & headpipes.. Make sure the exhaust valve servo motor is working correctly. Check the compression before doing anything.


  3. #3
    Thanks Randy. Compression is good. How do I check the servo motor?

  4. #4
    Randy........I am Shane the guy that called you from St. Louis you are having me call Seabold.......just wanted to thank you again for your time on the phone and let you know who I am on this site.

  5. #5 rgard32's Avatar
    Join Date
    Dec 2006
    Saint Petersburg,Florida
    unplug the valve actuator and apply power (12v) to the w/r(+) and w/blk(-) to open and reverse to close.... they will stay open if u leave it ride it and see if your rpms go up..

    also check to see if there opening all the way after you open them( try to push the valve up by hand)
    Last edited by rgard32; 09-04-2007 at 10:18 PM.

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