Craftsman 4 cycle gas trimmer(model 316.791970)?

I have the above trimmer. every now and then when trying to pull cord to start the cord will not pull. It seems to move about 6-12" then stops abruptly. After pulling harder it will finally break loose and pull. Just recently itwent a step further and the cord did not want to fully retract. In order to get it to retract you had to pull up a couple of times. I want to fix this but I am not sure which parts I need to start with. Not sure if part is the clutch and the other is the recoil spring. All help will be much appreciated.