Now this is a coincedence I just got a 7-19 Saturday, no spark either. The 17 looks similar. I got the rewind and flywheel off last night, not easy, not like a modern saw anyway. The best I can tell you is there is the rewind spring is wrapped, hooked, into a one way cam(?)that is on the crankshaft, I had to unwind the spring from the cam to get the housing and rewind pulley off in one piece. After that three screws for this cam and your at the flywheel. I hope you have a small puller for the flywheel, other wise I don;t know how you can get it off.
I was not getting spark because the coil wire was not making a good contact inside the coil itself. Everything esle was is in good shapeon this saw, amazingly, except the gas tank was full off old gas with a mix ratio of probaly 10 or 16/ 1, you could scrape the junk off the sides of the tank, stunk really bad too.
So I have to ask the question, is there anything I can do to get this coil wire sealed in good to make sure it stays in contact with the coil when I get the saw running or anyone have a coil to sell.
I hope this helps somewhat, I am no expert here, this saw is as old as I am.
Larry