I need help on carb adjustment

Ford Dave (MI) · Jun 22, 2016

I have a 1951 Ford 8N. How many turns out for the idle air and the main jet adjustment big knob screw on the carburetor? Thanks Dave

Royse · Jun 22, 2016

I start with 1 and 1/2 to 1 and 3/4 on the main jet.
If you need it out more than 2 turns you have problems
inside, not just the adjustment.

1/4 turn is usually good to start on the idle air screw.
Remember, that one adjusts air so out gives a leaner mixture.

Start it, let it warm up good and then adjust your main jet
to get good RPM and throttle response.
After that idle it down to less than 500 RPM and adjust the
idle air screw for the smoothest/fastest idle.

Readjust the idle stop screw and the main jet if needed.
You may have to repeat the process several times to get it
right where you want it.

steve19438 · Jun 23, 2016

hey royse,

that is for a MS carb? I want to print your instructions.

Royse · Jun 23, 2016

Steve, yes that would be for a Marvel Schebler.

I need help on carb adjustment

Ford Dave (MI)

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Royse

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steve19438

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Royse

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