Leaks will inevitably develop in your boat over time and you will need to use a sealant to fix them. However, not all marine sealants are suitable for each application. Read on and learn about the different marine sealants available so that you can select the most appropriate one when the need arises.
Polysulphide sealants are some of the most versatile sealants that are available for boaters who would like to fix an air or water leak on their vessels. Avoid using them on plastics because your boat's components will melt. It is also prudent to prime any oily wood before you use polysulphide sealants.
Polysulphide sealants are available in two forms. The first is the two-part polysulphide sealant. These are very strong and are ideal for caulking boat decks made from teak. They also need a shorter time to cure. However, they require a degree of skill to mix the two components well. One-part polysulphide sealants are the second type available. These are easier to use because there is nothing to mix before application. This sealant is also as durable as its two-part counterpart. However, it takes longer to cure.
Polyurethane sealants are the best to use when you want to create a permanent bond between surfaces due to their superior adhesion capacity. This makes them the option of choice in case you want to seal any gap in the deck or hull of your boat. However, polyurethane sealants shouldn't be used on certain plastics, such as Acrylonitrile Butadiene Styrene (ABS) and polycarbonates. Polyurethane sealants are second to polysulphide sealants in terms of adhesive strength.
Silicone sealants are known for their elasticity and high chemical resistance. These attributes make silicone sealants the material of choice when boaters want to work with metals that are different to create electrical insulation between those metals. Another key reason for the popularity of silicone sealants is that they can be used on the plastic components of boats. However, the major drawback of silicone sealants is that they don't form very strong adhesive bonds. It may, therefore, be unwise to use them on surfaces that are subjected to significant stresses, such as hull joints.
As such, each kind of marine sealant has its strong and weak points. It is wise for you to assess the requirements of each application so that you can select the most suitable sealant for the job. Consult a boat mechanic in case you are faced with a major leak.