Idle Mixture Screw Types

The two possible types of idle mixture (aka pilot) screw are fuel screws and air screws. If the screw is downstream of a passage that is fed only air, then it is an air screw. If the screw is downstream of a passage that has fuel connected to it (via the pilot jet), then it is a fuel screw. Fuel screws are usually located downstream of the slide, while air screws are usually located upstream of the slide. A fuel screw always has a washer and an o-ring under the spring. An air screw sometimes has a washer and an o-ring under the spring, sometimes has an o-ring groove in the screw, sometimes has no o-ring at all, and in the latter two cases doesn't use a washer. A fuel screw has a small tip with a step below, whereas an air screw has a blunter tip without a step. An air screw sometimes has an axial hole drilled through, whereas a fuel screw never has an axial hole. A fuel screw is oriented vertically or horizontally, whereas an air screw will be oriented horizontally or at an angle. If the carburetor is a CV type, the idle mixture screw is usually a fuel screw. The mixture is richened when a fuel screw is opened (turned counterclockwise), and leaned when it is closed (turned clockwise), whereas the mixture is richened when an air screw is closed (turned clockwise), and leaned when it is opened (turned counterclockwise).

High quality brass CNC machining, size and thread are very accurate One order contains 4 screws, including spring, high quality O-ring and bowl gasket

Weber DCOE IDF Carburetor idle air Mixture Screw 64755.007 with O Ring, Spring and Washer

Idle Mixture Screws - Adjustments and How to Purchase - Mikes

Purchase a L Series Idle Mixture Screw 35-0721 for your Harley-Davidson or Indian motorcycle from Vital V-Twin Cycles. Your source for V-Twin

L Series Idle Mixture Screw 35-0721 | Vital V-Twin Cycles

Idle Mixture Screw with O-Ring for Super E & G Carburetors (5 pack

Tips For The Perfect Idle-Mixture Screw Settings

IDLE AIR MIXTURE screws for Ford Motorcraft 2100/2150/4300/4350

Zenith V.05 075A Carb Query

Sales of Double barrel mixture adjusting screw - MEHARI CLUB CASSIS

Idle Mixture Screw 16-15

Rochester Quadrajet Carburetor Parts - Idle Mixture Screws & Springs

Replace the hard to get to stock slotted or “D” shaped screws with our custom made Idle Mixture Thumbscrews. Unlike other thumbscrews on the market,

Idle Mixture Screws Triumph Bonneville, Thruxton, Scrambler, America & Speedmaster

IDLE MIXTURE SCREW for WEBER 40 DCOE, DCOM, 48/50/55 DCO