We have a navy hull in salt water. We wax her every 6 month to hold down the oxidation. We love the navy hull but the maintenance is more expensive, but it is worth it in our opinion
We had the problem on our 2006 Motor yacht. The fresh water connection was not properly caulked and water was entering through the opening. The port window also needed to be recaulked and it corrected the problem.
[email protected] repaired our port engine with the same problem 680 hours. Antiono Drivilas is located just outside Jacksonville. He is excellent and about 1/3 of the price you were quoted.