I have a john deere bc1600 weed trimmer. it ran great for about a yr then it started acting funny. it wouldn't stay running after it had gotten warmed up. it runs great cold. I have already put on a new carb, ignition coil,cylinder,piston kit. nothing seems to help. I thought maybe the new carb was set wrong. tried readjusting carb worked good for about 10 -15 minute then started to loss power and stall out. What could the problem possibly be. I would like to know what the correct carb settings are for the high and low setting. not sure if thats the problem. I am out of guesses.