Announcement

Collapse
No announcement yet.

96 Yamaha Waverunner 760 Starting Problem

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

  • 96 Yamaha Waverunner 760 Starting Problem

    Hi all--

    I just picked up an older Yamaha 760 Waverunner (only has about 100 hrs on it), but it has a slight problem:

    If it happens to sit for over 3 or 4 hours it becomes hard to start. The strange thing is that if I let it sit, it will immediately fire up after pressing the green "Start" button, then die about a second after it begins to run.

    After it dies, it's hard to start. I have to keep pulling the choke lever in and out, and then it will finally fire. It's clear that the engine isn't getting enough gas, but I don't understand why it would start at first, then die. There must be some residual fuel in the float bowl. Once started, it runs great at any throttle setting. It'll restart right back up if I don't let it sit for too long.

    Any ideas would be appreciated. Should I change the fuel filter, or adjust pop off pressure? What exactly is the pop off pressure anyway? I'm a pretty decent shadetree car mechanic, but have only worked on fuel injection cars. This is my first foray into the world of carburetors aside from lawn mowers.

    Where is the fuel filter located on these things? Any pictures? Any manuals I can buy with regard to servicing? Thanks!

  • #2
    Re: 96 Yamaha Waverunner 760 Starting Problem

    Originally posted by awadecki
    Hi all--

    I just picked up an older Yamaha 760 Waverunner (only has about 100 hrs on it), but it has a slight problem:

    If it happens to sit for over 3 or 4 hours it becomes hard to start. The strange thing is that if I let it sit, it will immediately fire up after pressing the green "Start" button, then die about a second after it begins to run.

    After it dies, it's hard to start. I have to keep pulling the choke lever in and out, and then it will finally fire. It's clear that the engine isn't getting enough gas, but I don't understand why it would start at first, then die. There must be some residual fuel in the float bowl. Once started, it runs great at any throttle setting. It'll restart right back up if I don't let it sit for too long.

    Any ideas would be appreciated. Should I change the fuel filter, or adjust pop off pressure? What exactly is the pop off pressure anyway? I'm a pretty decent shadetree car mechanic, but have only worked on fuel injection cars. This is my first foray into the world of carburetors aside from lawn mowers.

    Where is the fuel filter located on these things? Any pictures? Any manuals I can buy with regard to servicing? Thanks!
    I've had the same problem with my 97. I got it used 2 seasons ago. After taking it to a dealer, they said that it was a known problem and that even Yamaha's fix may not work. I have been able to get around it by using a trick that someone else mentioned to me.

    When you open the engine bay (while facing the guages), on the right hand side you will see the black air filter (above the carb's and near the fuel filter). There is a small black screw hole at the top of the air filter. If you pour a small amount of fuel in there before you try to start the engine, the engine will start right up! That puts a small amount of fuel right at the carb's and that primes the rest of the fuel line. I also have a hand fuel pump, but this hasn't worked.

    My procedure for a cold start is as follows:

    - Fill the jetski with gas/ oil as needed
    - Turn the gas on and pull the choke up.
    - make sure that the kill switch is in.
    - Press and hold the green start switch until the engine starts and stay's on. If you simply press the start switch, the engne will try to turn over and will not stay on.
    - Turn off the choke after the engine is on.

    Comment


    • #3
      Re: 96 Yamaha Waverunner 760 Starting Problem

      I had the same problem. I eliminated the choke and added a primer kit. I no longer need to squirt gas directly into the spark hole to make it start. Using the primer, I now pump (about 5 pumps) raw gas directly into the carb throat. It starts right up.

      Comment


      • #4
        Re: 96 Yamaha Waverunner 760 Starting Problem

        where did you get that primer kit?

        Comment


        • #5
          Re: 96 Yamaha Waverunner 760 Starting Problem

          I got it here:

          http://www.jetskimechanic.com/

          Comment


          • #6
            Re: 96 Yamaha Waverunner 760 Starting Problem

            one reason they do this is that the fuel is lower than the engine if the tank is low so you get air in the line. Pouring gas or starting fluid to turn over the engine will pull the gas from the tank, or using a primer kit. When cranking, you have to pull the fuel from the tank. I have the same thing happen on my GP760. Its not really a problem, just a pain. Another thing is that it may start with the fuel that was in the carb, but have air in the line so when you put them in the water, they will die and not start easy, so let it run for about 10 secods to ensure that fuel is coming from the tank before putting them in the water, and another trick is leaving the fuel shutoff on ON.

            Comment


            • #7
              Re: 96 Yamaha Waverunner 760 Starting Problem

              Yep to air in the lines. I put a boat in-line primer on my gas line. It helped.

              What really helped was the pump primer that squirts gas directly into the carb throat.

              Comment


              • #8
                Re: 96 Yamaha Waverunner 760 Starting Problem

                Could this be related to the problem I'm having w my '96 Yamaha Wave Raider? Engine has been rebuilt - only about 6 hours on it when I bought it. Ran fine for about 6 hours until it suddenly kind of idled down and stopped - like it was out of gas. It had a 3/4 of a tank - topped it off - but no go. Then I changed plugs - it will turn over, but not start. Switched to reserve and used choke, but it will not start. Had someone check compression - was told this was fine.

                Any suggestions? Should I replace fuel line to see if this will help? What about fuel filter. I have a little experience with older car motors, but nothing on 2 cycle engines.

                Thanks.

                Comment


                • #9
                  Re: 96 Yamaha Waverunner 760 Starting Problem

                  hey yea i just got a 98 gp 760
                  i am getting a primer kit and carb rebul kit from dennis kirk its real cheap
                  does yours seam to ride ruff
                  i love th ski but when i took it out today it seams to bounce across the water
                  any suggestions

                  thankx

                  Comment


                  • #10
                    Re: 96 Yamaha Waverunner 760 Starting Problem

                    You stated:

                    >Could this be related to the problem I'm having w my '96 >Yamaha Wave Raider? Engine has been rebuilt - only >about 6 hours on it when I bought it. Ran fine for about 6 >hours until it suddenly kind of idled down and stopped - >like it was out of gas. It had a 3/4 of a tank - topped it off >- but no go. Then I changed plugs - it will turn over, but >not start. Switched to reserve and used choke, but it will >not start. Had someone check compression - was told this >was fine.

                    Hey, mine has this same problem. Rebuilt engine, idled great for 30 minute break-in. I then tried 1/4 throttle. The engine ran then stumbled and died. I used a spark checker and had NO SPARK. After it sets, it will start, then run for about a minute or two then NO SPARK. I'm sure the problem is in the ignition. When it refused to run on the last engine, the problem was a severed stator wire. The flywheel cut the wire. The so-called mechanic that installed the engine forgot to install the clamp that secured the wires to the inside of the cover. I'm not sure what the problem is now.

                    Comment

                    Working...
                    X