Results 1 to 6 of 6
  1. #1

    Angry 1999 Kawasaki 900 stx PLEASE HELP

    Hello, I have a '99 STX 900 with 68 hours on it. The problem is the exhaust after the blue/green pipe gets hot and melts the hoses. I bought one of those thermometer guns and took it over to the boat ramp. The blue/green pipe stays around 85 degrees. The exhaust after that got up to 105 - 110 degrees. This was mostly at idle. Last weekend the hose that connects the blue/green pipe to the rest of the exhaust blew. It took about 30 minutes of normal riding to let go. Would anyone have an idea why this is getting hot? The temperature warning does not come on so I know the engine is getting enough water but not the muffler.

    I had the same problem last year. Took it to a place and they had to suck out a bunch of sand and stuff. Then it worked fine up until this started happening again.

    I replaced the hose and it blew it again when I took it out yesterday because i didnt know if it was the hose. Since that was the original hose. My thoughts are now either the muffler or impeller is not suckin in enough water. I'm buying a new muffler and buying silicone hoses. If that doesn't work then I'm gonna get the impeller done. Also it looks like I'm gonna have to cut some of the ski to get the muffler out. Anyway around that?

    Any other suggestions? I took out all the hoses and checked for blockage so that can't be it.

  2. #2
    Banned User
    Join Date
    Jun 2010
    Milwaukee WI
    You most likely have something plugged up in the pipe. There should be some smaller hoses that inject water directly into the pipe. Where those hoses connect I would guess the fittings are removable. Your blockage is most likely in one of those fittings. I am not too familiar with the Kawasakis, but looking at the parts diagram and seeing how it all connects leads me there. The pipe itself stays cool because its also water jacketed, but the hoses and muffler/waterbox are cooled by the water that is actually injected into the pipe. Somewhere along the way, I am willing to bet the water is not getting inside the exhaust system.

  3. #3
    You don't have to cut the ski to get the muffler out... Unfortunately, you probably have to remove the engine. (On every Kawasaki ski I have owned you do...) and yes, make sure all of the hoses are clear and blow out all of the fittings in the muffler. sounds like a stoppage somewhere.

  4. #4

    Join Date
    Apr 2007
    Surprise, AZ via NorCal
    Follow the water inlet line from the jet pump thru hull fitting to under the exhaust pipe. There is a brass reducer tee fitting that goes from 1/2" to 3/8". This is typically where the debris is present. Youl'll need to remove the hoses and inspect. If that was not it, follow the 3/8" hose to the stator cover and remove the two 90 degree brass fittings and inspect those. Lastly, follow the 3/8" hose exiting the stator cover to the pipe. Remove the brass 90 degree fitting in the pipe and inspect. Also, look into the hole in the pipe to ensure no debris is blocking the cooling passage.

    Click image for larger version. 

Name:	cooling.jpg 
Views:	600 
Size:	68.5 KB 
ID:	302786

    Did you try flushing it?

  5. #5
    steve45's Avatar
    Join Date
    Feb 2008
    You need to install a strainer.

  6. #6
    Thank you so much everyone! I will update this thread after I do everything you suggested and get a chance to test it.

Thread Information

Users Browsing this Thread

There are currently 1 users browsing this thread. (0 members and 1 guests)

Similar Threads

  1. 1999 Kawasaki 1100 STX - Dead Cylinder - need help
    By Mbrundige in forum Kawasaki PWC Performance (2-stroke)
    Replies: 24
    Last Post: 04-05-2017, 10:58 AM
  2. 1999 kawasaki 1100 stx engine bay flooding ???? HELP
    By rangrs211 in forum Kawasaki How To & FAQs
    Replies: 7
    Last Post: 09-06-2014, 09:25 PM
  3. Please help! 1998 kawasaki 900 stx
    By Robinslu in forum Kawasaki How To & FAQs
    Replies: 5
    Last Post: 08-03-2013, 10:43 PM
  4. 2000 Kawasaki 900 stx
    By ej79 in forum Kawasaki PWC Performance (2-stroke)
    Replies: 0
    Last Post: 06-04-2009, 03:56 PM
  5. Your Theories on 2001 Kawasaki 900 STX problem?
    By cyphertext69 in forum Kawasaki Open Discussion
    Replies: 2
    Last Post: 08-04-2008, 08:17 AM

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts