With bowl cover inverted, distance between cover gasket surface and float (at center) should be as listed in the YH spec chart below. Adjust by bending float arm as required.
To adjust float drop, invert cover to upright position as shown in image, allowing float to hang down. Distance between cover gasket surface and bottom of free end of float should be as listed. Adjust by bending tang on hinge end.
Insert gauge in place of metering rod. With throttle valve tightly closed, press down on diaphragm shaft until metering rod arm contacts lifter link at diaphragm stem. With diaphragm shaft held in this position, metering rod pin must rest lightly on metering rod gauge (T109-104). To adjust, bend metering rod arm.
There is no adjustment provided. If acceleration is not satisfactory, examine diaphragm for wear or damage. Clean and blow out all passages. Replace worn or damaged parts.
With choke coil housing removed, have choke valve tightly closed and with fast idle link on high step of cam. Adjust choke connector rod to give the clearance listed in the YH spec chart between edge of throttle valve and carburetor bore (side opposite idle port). To adjust, bend fast idle connector link at curvature.
Hold throttle valve wide open and close choke valve. There should be the clearance listed in the spec chart between lower edge of choke valve and inner wall of air horn. To adjust, bend choke shaft unloader tang.
Loosen choke coil housing retaining screws and rotate housing by hand to the setting listed in the spec chart. Hold in position and tighten screws.
With engine at operating temperature and stopped, make sure choke valve is wide open and throttle valve fully closed. Start engine and run at a fast idle speed (85 rpm). There should be the clearance listed in the YH spec chart between throttle valve lever and dashpot bolt. To adjust, hold wrence on flat of diaphragm stem and turn self-locking bolt as required to obtain the proper clearance.
