Zenith 28 Carb

I'm having a problem with my Idle Adjusting Needle.
When I adjust it all the way in, it doesn't stall the engine.

I have adjusted the float to the manual's spec. I tested it by blowing into the fuel intake and raising the float and it closes normally.
I have a fuel regulator on it and have it adjusted to 3 lbs. I tried with the regulator at 1 lb. and the idle adjustment needle still didn't stall the engine.

With the needle out one turn, I have 19 lbs of intake vacuum. Turning the needle in or out doesn't increase the vacuum.

Thanks for any help,
John Seymour

The Zenith type 28 has an inverse idle circuit. Adjusting the screw all the way in is the RICHEST adjustment.

The later type 228 has the normal idle circuit where adjusting the screw out makes the mixture richer.

Jon.

The Zenith type 28 has an inverse idle circuit. Adjusting the screw all the way in is the RICHEST adjustment.

The later type 228 has the normal idle circuit where adjusting the screw out makes the mixture richer.

Jon.

How would you adjust it?

Suggested initial setting is 1 turn from fully seated.

From there, turning in (clockwise) is richer, out (counterclockwise) is leaner.

Jon.