Yeah, there's a bushing....
Servalite is the brand I use. I get them in packs of 10. You can buy individually if you want. Mine came from the local Do-It Best hardware store. Ace can get them too.
IMG_20140704_164303.jpgIMG_20140704_164316.jpg
Here's a thread by DX3 on it too.
Did you try adjusting the carb. Sounds lean to me. (Which is the same as too much air.) But it may adjust out. IDK how loose your throttle shaft is.