I once owned a 1976 Hunter 27. There were quite a few of them around, they all had water in the bilge. Deck leaks I was told. Then my keel tried to fall completely off. After repairing that and installing a nice new automatic bilge pump, we found that we only needed to vacuum out the dust bunnies and we were good to go! The new owner called me 8 years later because he also vacuumed the bilge every year, and suddenly he heard the pump running for the first time! He couldn't fugure out what the noise was. It turned out the rubber bedding under the huge stainless plates I added had actually dry rotted! He replaced that and all was well again.
Gary H. Lucas