there are a lot of posts on this....the boat is over 20 years old and may have soaked up some water in the transom and stringers...they are made of wood and screws/bolts holes leak over time and let water in.......my 88 is in that category and items are currenly being replaced ..... its a lot of work....but even new Grady's sit low.....if they are just low but draining well...it is what it is and I wouldn't worry,,,,but if you're not draining and standing in water you may need to dig deeper...literally....also, check the engine bracket for water if you have one...many times these extended brackets fill with water due to the caulk giving up around the access holes and thru bolts. There are drain plugs underneath. Make sure your scupper drain hoses are in good condition and clear of debris...replace and double clamp as well...if it gets stinky in the bilge even after using cleaner, like something is dying down there, and there's no standing water, the wood may be starting to rot....hopefully not, but be prepared for this news....good luck