Hello all! I was given this Jonsered and I'm having trouble nailing down exactly what it is without pulling the jug. Has compression, but runs a bit rough. What throws me is the air filter, which from what I see on the net is from a 670, but the carb might be a 630? Intake manifold from a 625? The tag is missing, so that doesn't help. I want to either get a carb kit, or the right carb before rebuilding it as it sat in a corner for years before I received it. Any info is greatly appreciated, thanks!