Originally posted by PatinIdaho
I use mach7 15% fuel same engine as you. I could not get to idle for more then 20 seconds inverted for a while either. After running about a gallon through it now it will idle for about 2 minutes before loading up and dying. I have tried leaning it out more but that does not help and makes it worse. I think it need more run time still as it keeps gettign better but slowly
Pat
3
Ran almost two more tanks through it today. With no more adjusting I got a minute and 25 seconds, tweaked it a bit and got a minute 30. Looks like you are right. The engine is still too tight. Oil from the exhaust is still very dark. I have run about a gallon and a quart through it. The ThunderBolt plug is still the best by about 15 seconds. On the GP Dr-1 the tank is at the center line of the crankshaft, since the engine is tilted only 45 degrees between horizontal and inverted the carb is slightly below the tank stopper, but they have compensated by sloping the back of the tank down so the center of the tank is about the center of the carb. Tweek it just a screwdriver length lean and it only runs a little less than a minute.