That happened on our '91 h 30. Compression post is aluminum but counter weight looked like it was cast iron and about 18 inches long. I pulled the compression post when the mast was down and had to beat the counter weight out. The tolerance is tight so the weight doesn't act like a bell clapper. Mine rusted tightly in place due to salt air and rain coming in the mast, following the mast wiring down through the conduit that was in the mast base and penetrated the deck into the salon and ran down inside the post. There was no drip loop in the wiring and no caulking in the conduit. I thought about grinding the weight clean and maybe coating it in oil, but ended up tossing it. The salon table was easy enough to move without it. Looked like the weight was slightly "swollen" from the rust that formed.
Edit...The foot of the compression post sat on a cross piece of fiberglass that was pretty beefy, but ended up having a wooden core so the lag bolts that held the foot secure had something to bite into. The wood was rotted in the holes. I oversized the holes and filled with west thickened epoxy and redrilled the holes.