wind a rag on a suitable blunt ended dowel or rod and rotate in the
hole to clean the rubbish off the wall of the hole. a good torch needed to see in. This is to remove obstruction BEFORE freeing the washer.
grind very small nick in the edge of the end of a small screw driver to act as a small barb. you can enter this into the hole and use the nick to 'snag' the washer on its inner edge as you pull it out.
once partially lifted you can easily remove. cleaning first ensures it won't jam on the way out. patience.
rog
March 2008