Marine Fouling Paint

It is the obligation of trained marine mechanics to make yard crews aware of this important bit of information. Proper application of anti-fouling paints can save the customer money and give us less aggravation when it's time to tear down a lower unit for repair.

Fouling is a build-up (usually animal-vegetable-derived) occurring on the boat's bottom and drive unit. Fouling creates drag, which reduces boat performance. In fresh water, fouling results from dirt, vegetable matter, algae or slime, chemicals, minerals and other pollutants. In salt water, barnacles, moss and other marine growth often produce dramatic build-up of material quickly. It is important to keep the hull as clean as possible to maximize boat performance.

Anti-fouling paint, if required, may be applied to boat hull observing the following precautions.

WARNING: DO NOT paint zinc or aluminum anodes or any Electronic Galvanic Corrosion System reference electrode and anode, as this will render them ineffective as galvanic corrosion inhibitors. Avoid corrosion damage. Do not apply anti-fouling paint to the stern drive unit or transom assembly.

paint-foul.gif (4302 bytes)

Avoid an electrical interconnection between the stern drive, Anodic Blocks, or any Electronic Galvanic Corrosion System and the paint by allowing a minimum of 1 in. (26mm) UNPAINTED area on transom of the boat around these items.

IMPORTANT: If anti-fouling protection is required, Tri-Butyl-Tin-Adi pate (TBTA) base anti-fouling paints are recommended on stern drive boating applications. In areas where Tri-Butyl-Tin-Adipate base paints are prohibited by law, copper base paints can be used on boat hull (other than aluminum hulls) and boat transom. Corrosion damage that results from the improper application of anti-fouling paint are not covered by warranties.

There are special anti-fouling paints and epoxy coatings, on the market, for coating exposed stern drive surfaces. Check with your local dealer for what is recommended for your area.

Also, Volvo stern drive owners should be careful about painting their drive units. Painting some parts on AQ series stern drives can cause reverse-lock failure. Owners of the new "composite" stern drives should contact Volvo for recommendations before re-painting their drive unit.