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98 saltwater series carb issues

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  • 98 saltwater series carb issues

    I replaced my needles and pilot screws because I could not get engine to idle right. Now it will idle on the hose but not in the water. I took boat home and ran motor. I put my hand over each carb. The two top carbs had no pull and engine did not die when I covered them. The bottom one did. My Manual gave me the float hight measurement, which I followed( measurement when needle is seated) It did not give me the float drop measurement( how far needle should come out of the seat) so I set the Floats so that they would open up alot and pull the needle up high. When I did this the carbs would dump fuel out the tops and the high speed jets alot. So I took the carbs apart and minimized the float drop so that the needle would only come out of the seat a very very small amount. After I did this, the carbs would hold fuel and my primer would get hard with no fuel overflow. I think two carbs may not be working because the floats are not comming up enough, but my bottom carb that is working should be about the same as the other two carbs. Any ideas about how much the needles should be moving? I have spark and compression.

  • #2
    Any idea how much needles should come up?

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    • #3
      floats should set at about .063" with the gasket installed and the carb upside down.
      no float drop spec.
      but with no vacum it wont work/.
      did you test the compression and inspect the reeds?

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      • #4
        Compression is 120 on all six holes. I was cruising around last week at around 40 mph so those cylinders had to of been firing then. It just wouldn't idle very well, so I suspect it is something I did to the carb when I put it back together. Will it make a didference if the float drop is very small or has alot of travel? Could also be vacuum issue, do reeds come right out when carbs are off?

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        • #5
          Does there need to be the right carb settings/fuel to create the vacuum, or does there need to be vacuum to creat the right fuel amount?

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          • #6
            Without suction the cylinder can not pull in the air and fuel mix it needs

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