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  1. #1

    Default Nissan 1994 Model Ns30a3 RUNS ROUGH AT SLOW SPEED

    I Have Fixed A Lot Of Stuff On This Motor And Everything The Guru Has Told Me To Do Was Right On Target. Regretably A Lot Of The Stuff I Did He Did Not Recommend. I Replaced The Fuel Pump, Water Pump. Gear Case Seals And Cleaned The Bowl On The Carb. My Original Problem Was Cut Out At High Speed, The Carb Bowl Was Loaded With Varnish And Crap. Now It Runs Fine At High Speed But Smokes At Start Up And Runs A Little Rough At Slow Speeds. I Feel It Is Running To Rich At Slow Speed. If The Float In The Carb Was Not Adjusted Right Or Fuel Soaked, Could This Be Causing My Problem? Or Is There Another Adjustment That Could Be Causing This?

  2. #2
    Captain pvanv's Avatar
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    Default Re: Nissan 1994 Model Ns30a3 RUNS ROUGH AT SLOW SPEED

    Float adjustment is certainly a likely culprit.
    Paul
    Certified TLDI Technician
    Buffalo NY USA

  3. #3

    Default Re: Nissan 1994 Model Ns30a3 RUNS ROUGH AT SLOW SPEED

    I Have The Factory Repair Manual And It States Check For The Proper Float Measurement When The Carb Is Inverted. But I Can Not Find Anywhere Where It States What That Measurement Should Be. Anybody Have An Idea What That Should Be.

  4. #4
    Captain deejaycee_2000's Avatar
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    Default Re: Nissan 1994 Model Ns30a3 RUNS ROUGH AT SLOW SPEED

    try the air/fuel mix first .......
    __________________________
    ... THE MAXIMUM HORSEPOWER IS NEVER ENOUGH ...

  5. #5
    Captain pvanv's Avatar
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    Default Re: Nissan 1994 Model Ns30a3 RUNS ROUGH AT SLOW SPEED

    While you're at it, be 100% sure the emulsion tubes, etc, are perfectly clean. Possibly needs a more thorough carb cleaning. Float spec should be in the Factory service manual. Rule of thumb: Floats should look parallel to the upper carb body when the carb is inverted.
    Paul
    Certified TLDI Technician
    Buffalo NY USA

  6. #6

    Default Re: Nissan 1994 Model Ns30a3 RUNS ROUGH AT SLOW SPEED

    Thanks To Everyone For Their Input, This Carb Has No Adustment For The Float Level. The Float And Lever Which Holds The Arm Pin Float Is Plastic And I Cant See How You Could Adjust This In Any Way. I Thought I Had The Carb Clean But There Is Still Some Small Specs Of Trash In There, Its Tough To Get Out. I Assume The Adjustment Screw Is For Air Fuel Mixture.
    I Have A Carb Kit Coming. Hopefully This Will Fix All Of My Problems.

  7. #7

    Default Re: Nissan 1994 Model Ns30a3 RUNS ROUGH AT SLOW SPEED

    I have a 15 horse Nissan- what you are describing sounds exactly like what is happening to me .... Have you figured it out yet? Was the carb the problem?

  8. #8
    Captain Sea Rider's Avatar
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    Default Re: Nissan 1994 Model Ns30a3 RUNS ROUGH AT SLOW SPEED

    If the engine was heavily used, torque head gasket to see if under specs would be suggested, check plugs if with 1.0 mm tight gap.

    Happy Boating

  9. #9
    Petty Officer 2nd Class basstracker219's Avatar
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    Default Re: Nissan 1994 Model Ns30a3 RUNS ROUGH AT SLOW SPEED

    try the air-fuel mix before starting.

  10. #10
    Captain pvanv's Avatar
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    Default Re: Nissan 1994 Model Ns30a3 RUNS ROUGH AT SLOW SPEED

    Quote Originally Posted by HERRDON View Post
    I Have The Factory Repair Manual And It States Check For The Proper Float Measurement When The Carb Is Inverted. But I Can Not Find Anywhere Where It States What That Measurement Should Be. Anybody Have An Idea What That Should Be.
    The float should be perfectly level when the carb is inverted.
    Paul
    Certified TLDI Technician
    Buffalo NY USA

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