thru hull fittings

New to any hull work. Last year at the end of the season the heater did not work. Upon inspection when out of the water I noticed that the bronze water intake fins were broken so I bought a new one. The new one has four screw holes in it. I assume the old one does to. Can anyone go through...

I am looking to replace the plastic thru hull fittings on my 99 340. I have read a lot of reviews on here - some say it's painful to remove them because of the sealant that was used. I don't mind the hard work my bigger question is where are the 3 located on the port side of the bow - how and...