Welcome Guest - Sign Up today
Welcome Guest - Sign Up today

Announcement

Collapse
No announcement yet.

98 Yamaha xl760 overheating

Collapse
X
  • Filter
  • Time
  • Show
Clear All
new posts

  • 98 Yamaha xl760 overheating

    I have a 98 Yamaha xl760 that overheats at full throttle, but is fine I you keep it under 30mph. Also noticed that there is almost no water shooting up in the roostertail. I checked underneath and there are no obstructions in the intake. Sounds silly I poured water down where the roostertail comes out and it drained right out into the jet. Anyone have any ideas?

  • #2
    Re: 98 Yamaha xl760 overheating

    Any ideas? My kids are dying to get out on the water.

    Comment


    • #3
      Re: 98 Yamaha xl760 overheating

      You should have a telltale port somewhere that should be putting out water (not the rooster tail). If you are not getting output from that port, you have an obstruction somewhere.

      Check the output and trace the cooling lines for kinks or obstructions. you can disconnect them and blow through them..

      You may also be getting a lean condition at the higher speeds. This can be a fatal condition for the engine, with the higher temps being the telltale. When were your carbs cleaned readjusted last??
      The democracy will cease to exist when you take away from those who are willing to work and give to those who would not.

      -Thomas Jefferson

      Comment


      • #4
        Re: 98 Yamaha xl760 overheating

        The carbs were cleaned back in the spring. What do you mean by "Lean condition"? I do have water coming out the cooling port on the side, and it REALLY hot. I'm wondering if it can be an impelllor problem, as the line that pulls the water up for the rooster-tail is connected straight to the jet on the back....it's not hooked to any pump. I'm wondering if I'm getting cavitation in there and at slower speeds it's still getting enough water to cool, but at higher speeds it's not? If iwas getting any cavitation would I hear or feel anything different?

        Any thoughts?

        Comment


        • #5
          Re: 98 Yamaha xl760 overheating

          You have low speed adjustment on your carb and a high speed. I don't profess to be an expert in Mikuni carb tuning, but it is possible to have the correct amount of fuel at low tomide speed and to have not enough (lean) at mid to high. The absence of oil in the high end lean could cause higher temps and eventual seize.

          Again not an expert but if you have enough water pressure to go fast, one would think it would be enough to supply the input water as it siphons off the jet thrust. I would trace each line from the nozzle forward. Disconnect the hoses and ensure they are clear and there are no kinks.


          Where do you boat? Salt or fresh..
          The democracy will cease to exist when you take away from those who are willing to work and give to those who would not.

          -Thomas Jefferson

          Comment


          • #6
            Re: 98 Yamaha xl760 overheating

            Originally posted by tankengine View Post
            The carbs were cleaned back in the spring. What do you mean by "Lean condition"? I do have water coming out the cooling port on the side, and it REALLY hot. I'm wondering if it can be an impelllor problem, as the line that pulls the water up for the rooster-tail is connected straight to the jet on the back....it's not hooked to any pump. I'm wondering if I'm getting cavitation in there and at slower speeds it's still getting enough water to cool, but at higher speeds it's not? If iwas getting any cavitation would I hear or feel anything different?

            Any thoughts?
            remove pump cover and check all cooling lines to make sure they are in good shape, not kinked or clogged.

            Comment


            • #7
              Re: 98 Yamaha xl760 overheating

              Hi. I know this is an old one. But would like to know how you made out. Mine is doing the same. I checked all lines are good and blow fine . I also let it run at the dock for 20 min and fine but if i drive it after 5 min it gets the red light temp. But if i ride slow it runs fine. The only thing i can think of its i have to much oil in the gas and running lean. I rode for about 5 miles and ran fine under 30mph
              P.s is the line that goes into the intake coming from exhaust is it suppose to be hot.

              Thanks you for help.
              98 yamaha xl760

              Comment


              • #8
                Re: 98 Yamaha xl760 overheating

                Also i feel like the squirt hole on the side at high rpm is doesnt have enough pressure and water comes out kinda hot

                Comment


                • #9
                  Sign up today
                  Re: 98 Yamaha xl760 overheating

                  Oh sorry does it have a thermostat

                  Comment

                  Working...
                  X