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  • No power past half throttle

    Hello,

    I have a 1996 115hp engine. I recently fixed an oil problem thanks to some help on this forum.

    Since the problem with that was fixed it has run perfectly. But the last few times I have started it I noticed it has taken a little longer for it to start. I actually have to pump the primer to start now where I have never had to do that before. So I am assuming the gas is not staying in the line but rather feeding back to the tank. The last time out it was runing great for a nice long run when all of a sudden it was bogging and I could not get anything much past half throttle out of it. It sounds like it is starving for fuel. When on the hoist out of gear I can rev it up but it is breaking up at top end like a miss fire. Where would I start to diagnose something like this?

    Thanks

  • #2
    it sounds like the little ball in the primer in fulling sealing shut

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    • #3
      Originally posted by yamaman25 View Post
      it sounds like the little ball in the primer in fulling sealing shut
      That is where I am going to start. I will be picking up a new primer ball and gas line tomorrow.

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      • #4
        Still need help

        Today I checked the compression. 110 across all four cylinders which was a welcome relief. Changed the plugs out as long as I was there but they all looked to be burning clean. New gas line and primer bulb. And the filter looks to be clean.

        Still doing the same thing.

        I am not sure of where to look next. Any ideas?
        Last edited by nasdaqsam; 07-19-2009, 07:28 PM.

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        • #5
          sounds like either a fuel pump or dirty carb problem. may want to check pump first, since that would be a fairly quick and inexpensive fix. Good Luck!

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          • #6
            Originally posted by robert graham View Post
            sounds like either a fuel pump or dirty carb problem. may want to check pump first, since that would be a fairly quick and inexpensive fix. Good Luck!
            Is there anyway to test this with out just replacing it? I don't think is would be the carbs, they were rebuilt recently and it has run perfectly since and the filter is clean as clean can be so there does not seem to be a problem there.

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            • #7
              Resolved....I hope.

              Well, pulled the gas line tonight and pumped a bunch of gas into a jar. Zero water. Drained the carbs, same things. However a little odd that there was no gas in the upper left carb. I pumped the ball a few times and got gas out of it. Put it all ack together and took her for a spin. Runs great........I don't get it.

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              • #8
                I feel like I am talking myself here but if this helps others it's worth it.

                I spoke to a boat mechanic on the carb with no gas in it. He was thinking the needle may have been stuck due to ethanal. When I pumped the ball with the screw open it broke the needle free and allowed gas in. Sounds reasonable.

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                • #9
                  maybe a stuck float needle valve in that carb with no fuel in it. do you run the Stabil Marine all the time and a fuel/water seperator? anyway, sounds like it's fixed for now. Good luck!

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                  • #10
                    Originally posted by robert graham View Post
                    maybe a stuck float needle valve in that carb with no fuel in it. do you run the Stabil Marine all the time and a fuel/water seperator? anyway, sounds like it's fixed for now. Good luck!
                    I put stabilzer in but not often enough. From now on I will be. I am going to put a seperator on it also just for safety. Thanks
                    Last edited by nasdaqsam; 07-21-2009, 07:51 PM.

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