Very comprehensive repair thread here: Husqvarna 50/51/55 repair thread. They are both connected to the intake partition that the carb is connected to. Nipple sticks in the cylinder usually.
I've come across a couple of those and fixed them up and sold them to buddies that had never had a "real" saw before. My neighbor got one of them I fixed and he loves it. I had done a mild MM on it for him. He cuts a lot of wood with it heating his house with an older outdoor burner. He goes through about 15 cord a year and I'm trying to get him on the 3 year plan instead of the 3 week and sometimes 3 day plan that he's on now... He loves his stinky burner cuz he can burn anything in it. I'm glad we're not down wind. I gave up on convincing him that he would be burning way less wood if it was nice dry stuff. At least he has an OK saw now to cut all that wood.
