I set the low idle on my carburetor this evening using the instructions from the secret file, but I still have an issue. The motor will idle at 750 rpm for about a minute and then it spits back "hard" and dies. I started it back up and ran it at about 950 rpm and it ran for about 2 minutes then it spit back "hard" and died. It doesn't seem to be running rough while it's idling but then suddenly spits back and dies. It runs fine mid-range say around 1500 to 2000 rpm.