[rclampitt]

Recently purchased a Cal 31 Sloop with 16 hp Universal with fresh water cooling through a heat exchanger and salt water system. Subsequently sailed her offshore from Bellingham WA to Seward Alaska last month,1458 km. During voyage saltwater cooling system would fail in moderately rough seas and when pushed to over 5 knots. Have throughly checked impeller, hoses, and all connections. Opinions from various mechanics suggest pinhole leak in strainer gasket or hoses , to strainer too high above water line. No leaks apparent.

Any thoughts on this.