Here's the problem. When the engine is not running the throttle appears to close all the way. With the engine running it doesn't quite return to fully closed unless I let it snap close. Seems to hang up just slightly (1200-1500rpm)until I put a little thumb pressure on the linkage. Then it will drop down to 850. I put a stiffer spring on the linkage but it makes the gas peddle rather hard to push down. I just had the bushings replaced. Don't ya just love 37 year old carbs......