so, is it just that i need a new carbuerator? what is causing my engine to idle at 3500rpm? today it hit 4500rpm, and i'm getting worried. i can quick fix it by adjusting the idle speed screw, but that only works at that time, while it's on. cause the next time i start it up, it shoots right back up. if anyone has seen this before, let me know. i really don't want to buy a new carb, or rebuild. but, if that's what it is, then so be it. i would just like some input and wisdom on this here situation. thanks