Silicone Spray and Thru-hull Fittings
Another critical issue, also corrosion related, is regarding metal (typically bronze) thru-hull fittings and shut-off valves. These valves and fittings usually have a blue-green colour due to surface corrosion. These are critical items to look after, maintenance wise, as a failure can result in sinking. Surface corrosion can be kept at bay with an occasional spray from your can of silicone, much as with your electrical connections.