Thanks so much for your help. To answer your question, this carburetor
doesn't have a primer, that I know of. My lawnmowers have a little
bulb that you squirt to prime the carburetor, but there is no bulb on
this edger. I haven't tried any starter fluid, but I'm sure that I'm
getting a good spark. I don't think that compression is the issue,
because it ran fine before I put it away, and unfortunately, I had left
it with gasoline in the tank for a couple of years before pulling it
out last week and discovering that not only did I not empty the gas
tank before putting it away, but I also had not added any additive to
prevent it from gumming up the carburetor.
I'll pick up some starter fluid today and squirt it in the spark plug
hole, to see if it will run with it.