Adjusting PMO Carburetor

[marty5810]

When adjusting the fuel air mixture, when I got to the back right-hand side cylinder, when I screwed the adjustor all the way in, the engine revved up instead of being choked down. What would cause this?

When the engine was rebuilt, the carburetor sat for a year and a half, and the gaskets dried up and broke down. My engine builder cleaned things out and put on new gaskets. Does someone know what would cause this issue?

This is a 1982 911 SC 3 liter.

[stownsen914]

Just to confirm, which screw were you turning?

[3literpwr]

It's Webers, but this is a good video. https://www.youtube.com/watch?v=p3qwIbRdcvE

[marty5810]

Mixture screw #162

[1QuickS]

Good chance the mixture was overly rich and closing the mixture screw leaned the mixture to be closer to correct which will then cause the engine to run faster.

Idle jets may have been enlarged without erasing original size designation or the idle jet was not completely seated, either will create excessive fuel flow to mixture screw. It is possible that if you have a pre-1969 Weber body and the idle jet holder is designed for use with O-ring then this would cause idle jet to not properly seat.