hungrybare
ArboristSite Member
Hey guys, I need a little advice from the experts. one of my buddies has a Jonsereds 621 which pulls hard, ya know like it wants rip your arm out of the socket. Take the spark plug out and it turns nice and easy and really smooth. Not getting too much gas in the carb/ muffler not plugged so I checked the compression and it is 210. What woud you suggest to put in the cylinder to disolve any carbon that might be on top of the piston? Or any suggestions would be greatly appreciated. When it starts it runs fantastic. Sorry, could a moderator please move this to the chainsaw forum?