Hatch thoughts
At some point after my boat was built (1974), Catalina added a seahood to the sliding hatch, which, if the sealant is still good after 20+ years, should prevent leaks from the forward part of the hatch. I don't remember when that was, but I believe before '85. If so, (and your sealant is still good) then your leaks are not coming from the hatch, but from either:1. Hatch boards (try putting pipe insulation across the top hatchboard where it mates the companionway hatch, or for more bucks get a canvas covering for the entire companionway area).2. Hardware bolted thru the deck (winches, handrails, sheetstoppers, etc.)3. Some other gremlin far away place, relatively speaking: stanchions, shrouds, mast step, etc. that can drain to the main cabin. You'll see telltale signs of a leak from these places elsewhere in the boat.I've got a leak that I've been trying to chase down for 14 years, and it's evaded me to date. I just sigh and sponge out the bilge after a rain (I've got a '74 with the mild steel keel bolts, so YOU KEEP THAT BILGE DRY!)