Some of the chokes are adjustable by loosening a screw on the thermostatic coil mounting post, rotating it, and tightening the screw back down. The choke should be removed to determine which you have as it may have been replaced with an aftermarket unit.
Others are only adjustable by bending the rod between the TS coil and choke butterfly.
Or as Nitrous mentioned you may have the wrong choke / rod
On a cold motor (sitting overnite)
IF you remove disconnect the clip,
remove the rod from the choke
It should spring upwards.
If it does not, that is why the choke is not closing.
See above post.
from what I could see in your picture, the rod appears straight up which would indicate you may have an adjustable post, (see above)
Or you have the wrong Choke assembly and or Rod.
