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Carburetor Adjustment - Rochester 2g

Discussion in 'Early CJ5 and CJ6 Tech' started by Steve's 70-5, Jun 26, 2018.

  1. Jun 26, 2018
    Steve's 70-5

    Steve's 70-5 Active Member

    Louisville, Ky
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    Got a Rochester 2G. Ran it a little and it is running rich by the smell from the exhaust. When turning the screws to lean it some. How much of a turn will change things. 1/4, 1/2, full turn?
     
  2. Jun 26, 2018
    Focker

    Focker That's a terrible idea...What time? Staff Member

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    Look at the Technical Index page for the manual.
     
  3. Jun 26, 2018
    Focker

    Focker That's a terrible idea...What time? Staff Member

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  4. Jun 27, 2018
    blevisay

    blevisay Oh Noooooooooooooooo! Staff Member

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    Do You have a vac guage?
     
  5. Jun 27, 2018
    Steve's 70-5

    Steve's 70-5 Active Member

    Louisville, Ky
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    no
     
  6. Jun 27, 2018
    Steve's 70-5

    Steve's 70-5 Active Member

    Louisville, Ky
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    Bought a remand carb. Just need to lean it out a little I think.
     
  7. Jun 27, 2018
    blevisay

    blevisay Oh Noooooooooooooooo! Staff Member

    Portland Tn.
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    Turn screws in till it runs rough and back out 1/4 turn.

    If you decide to get a guage, do the above but tune for best vac.
     
  8. Jun 27, 2018
    colojeepguy

    colojeepguy Colorado Springs

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    This.
    It's not rocket surgery. Best lean idle should be all you need to do.
    Both screws should be at approximately the same setting.
     
  9. Jun 27, 2018
    Beach66Bum

    Beach66Bum 1966 Tuxedo Park Mark IV 2024 Sponsor

    Big Island on...
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    You can gently seat the needles closed and then back out 1 1/2 turns each to start. You may have to go to 2 turns. Like mentioned above, use a vacuum gauge for best tuning. You may also have to adjust the timing if the carb is way out.
     
  10. Jun 27, 2018
    Steve's 70-5

    Steve's 70-5 Active Member

    Louisville, Ky
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    Fooled with the carb tonight. Set timing 5-6 BTC. Adjusted the 2 carb screws (turned clockwise 3/4 turn) did not really notice any change. Decided to take the Jeep for a drive, but needed to adjust the clutch. Was under the Jeep adjusting the clutch, I notice some fluid dripping from the inspection plate on the back of the block. Oh great, not even a half mile on the Jeep and already have a leak. Thinking it was a coolant leak, I looked at the heater hoses lines running to the heater box. Well the leak was from a fuel line. I think the fuel was running down the block and while the engine was running, the fan was blowing air over the block. This was evaporating the fuel and blowing out the back of the Jeep by the exhaust. I was smelling fuel thinking the Jeep was running rich.

    I have the vinyl/plastic fuel lines that run from the tank to the metal lines on the block. I used a piece of rubber fuel line as a coupling, it goes over the metal line and over the vinyl line with hose clamps on each side. The leak was where the rubber line goes over the vinyl fuel line.

    Now I need to figure out a better connection there.

    Looking back I am lucky I did not have a fire.
     
  11. Jun 27, 2018
    Steve's 70-5

    Steve's 70-5 Active Member

    Louisville, Ky
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    Where can i get a vacuum gauge?
     
  12. Jun 27, 2018
    Focker

    Focker That's a terrible idea...What time? Staff Member

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    That happened to me, but it took me a while to find it. Gas was spraying a mist onto the firewall which was ruining the paint. I couldn't figure it out for a while, but I'm glad when I finally did. Misty gas under the hood is not a good thing.
     
  13. Jun 28, 2018
    blevisay

    blevisay Oh Noooooooooooooooo! Staff Member

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    Any Flaps or even harbor freight
     
  14. Jun 28, 2018
    OzFin

    OzFin Vintage Jeep Guy

    Michigan
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    I bought one of these, it works very well. You will be shooting for highest vacuum so the actual number isn't that critical...that being said the one I got seems to be reasonably accurate.
    Fuel Pump and Vacuum Tester
     
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  15. Jun 28, 2018
    Focker

    Focker That's a terrible idea...What time? Staff Member

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    Question:

    I would imagine that it's best to perform the vacuum/carb adjustment after the engine reaches operating temperature?
     
  16. Jun 28, 2018
    blevisay

    blevisay Oh Noooooooooooooooo! Staff Member

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    Yes
    The warmer the better.
    I am looking for a Vacuum guage chart also for y'all.
     
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  17. Jun 28, 2018
    Focker

    Focker That's a terrible idea...What time? Staff Member

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    Here's a video that I just watched. It has a lot of good information that may be very basic for some of you here. I feel pretty good about how I have my carb set, but after watching this video...I'm off to HF to buy a gauge and start over.

    Fast forward through the corny comedy if you have to, but give the video a chance.
     
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  18. Jun 28, 2018
    blevisay

    blevisay Oh Noooooooooooooooo! Staff Member

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  19. Jun 28, 2018
    blevisay

    blevisay Oh Noooooooooooooooo! Staff Member

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    Good Video Brad!
    I remember my dad running the gauge on many a customers wiper and driving.
     
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  20. Jun 28, 2018
    Focker

    Focker That's a terrible idea...What time? Staff Member

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