Remove the muffler and have a look at the piston and cylinder through the port. They are likely galled. You may be able to clean up the cylinder with muriatic acid and scotchbrite but the piston will need to be replaced, if you can find one.

Here is a link that might be useful: Homelite parts

omiakinbac
Have you checked your piston? I may have a good used one if you are interested.
Bill
785-562-3539