First thing...the choke is NOT fully open in that pic. Second thing, what you have circled is the AIR VALVE lock-out. The actual secondary throttle blade lock-out lever is down on the bottom. The design is for the secondary throttle blades to open with the throttle linkage(at 3/4-full throttle), and the air valve is controlled by the amount of air rushing past them with the throttle blades open.....like a variable venturi effect. The air valve assy keeps the engine from bogging down completely when the secondary throttle blades go wide open.
So...first thing I would do is adjust the linkage from the choke coil to the choke lever, and get it to be fully open with the engine warm. Then see if full throttle will open the secondary throttle blades. NOT the air valve( on top), but the throttle blades themselves. If the throttle blades are not opening, the air valve will not move either.
Sometimes, the little lock-out "tang" for the secondary throttle blades will gum up, of otherwise stick, and keep the secondaries from opening. You have to make sure the choke is opening fully when warm before doing anything else.
|UPDATED|6/7/2018 10:32:16 AM (AZT)|/UPDATED|
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