Been there done that
Brenda, I hauled my 82 C-30 (5411) this last winter and replaced the thru-hull screen, seacock (bronze), and installed a raw water strainer(small screen) purchased from west marine. The strainer I bought is about 1 quart in capacity. The boat didn't have one initially. The thru-hull is just like any other, haul the boat, remove the hose, remove the backing nut threaded onto the intake thru-hull screen. Also it's a good time to see if the thru-hull has been leaking. Bought a new thru-hull intake screen (1/2"), drilled the 4 holes for the bronze screws (do not overtighten, they break easily), installed backing nut, screwed new bronze seacock onto threaded portion of thru-hull, installed 1/2" fitting and hooked the hose back up. Works great and be sure to double clamp any hoses that go below the water line on thru-hull fittings. Hopes this helps.
