When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
Are you referring to the choke plate at the top of the choke tower?
If it won't open all the way when the engine is warmed up, you need to adjust the choke thermostat. To make it open farther, loosen the three screws that secure the thermostat housing and rotate the housing clockwise. Rotate it just far enough to open the choke completely with the engine warmed up to normal operating temp.