O-ring!
Thank you!
Here are pics of the springs with measurement. The shorter one was what I had in the air valve in the previous post, the longer one is the loose one in my previous post. The other pic is of the two with the carb and choke slide bring installed for reference. Ducatiman, your pics look like you have the longer of the two in the air valve? I am thinking the shorter one may be part no. 92081B but in the parts diagram it is not clear where it goes in the butterfly shaft assembly- this could be totally wrong.
Thanks again for the guidance.