Hull cleaning or “a hull scrub” as it is also known can be considered an integral part of any moored or berthed vessels maintenance program. Performed by experienced and qualified Commercial Divers, this maintenance begins with a visual or photo inspection, which identifies the condition of the key components that protect a vessels hull during prolonged water immersion.
What are the key benefits of having a regular hull maintenance program?
Boat speed: Even a light foul of algae affects the speed of the hull through the water. For motor powered vessels it initially manifests its presence at the top end of the vessel’s cruising speed with either a drop in boat speed for a given engine revolutions or a rise in engine revolutions to maintain your normal boat speed. For sailing vessels, every knot of boat speed is precious. Heavy infestations will affect all areas of your vessels operation.
Fuel Consumption: Tied closely to boat speed is fuel consumption. Dragging marine fouling around on your hull is akin to towing a sea anchor or drogue everywhere you go. In effect you will be asking your vessel’s motors to work harder, which you will soon notice at the fuel pump. More importantly it will shorten the motors working life and create a more frequent maintenance schedule.
What are some other important benefits of regular hull maintenance?
Aesthetics’: Every boat owner is “Boat Proud”. A hull clean will bring back the clean clear lines to your vessels waterline.
Hull Penetrations: Regular hull maintenance ensures that all hull penetrations are working correctly. Vessel speed log wheels can jam when fouled giving incorrect boat speed readings and depth sounder transducers may give inconsistent readings when fouled. Other penetrations such as engine cooling intakes can become blocked increasing the risk of your engine overheating.
Hardstand Option: Every few years all vessels should be removed from the water to have new antifoul protection applied. This operation, while necessary is time consuming and stressful to any vessel owner and the boat! A periodic hull inspection and clean at 3 monthly intervals will increase the duration between hauling out your boat saving you time and money. A maintenance program conducted by our professional dive team has a very low impact on your vessels hull and can be conducted without the skipper or owner being present.
What are the most common effects to a boats hull due to prolonged immersion in salt or fresh water?
Marine life: Barnacles, mussels, and other small marine animals attach themselves to your boat's bottom while it's sitting in its slip or at its mooring. These animals can multiply like rabbits, covering the boat's bottom quickly once they get started. The hard-shelled creatures that grow on boat hulls are primarily filter feeders, meaning they grab bits of food that drift by in the current. A boat moored where there is a strong current flow will have more trouble with crusty critters on the hull than one in more stagnant waters.
Plants: Weeds and water plants can also attach themselves to the boat, most often near the waterline where there's plenty of sunlight.
Algae Slime: Algae can form a mess on your boat's bottom, blooming rapidly and creating an environment that attracts other organisms. This creates a nasty, hard-to-clean situation, and slows your boat tremendously when it's moving through the water.
What about the Props?
Propellers: Constructed most commonly from Bronze, Aluminium or Stainless Steel, your vessels propellers have their own maintenance considerations. A prop with bent or chipped propeller blades is less efficient, and the motor driving it will use more fuel than the same motor fitted with a good propeller. Damaged propeller blades can often be straightened and welded, and the prop re-pitched and balanced for less than the price of a new propeller. Propellers will also attract marine life that will decrease the efficiency and life of the blades if not cleaned and protected regularly. Our divers inspect and clean propellers as a part of any hull maintenance program but we can also remove the propeller when required and through our trade service suppliers have any propeller revived to near new condition. We strongly recommend the use of an antifouling agent such as Prop Speed on your propeller to extend its life and ideal characteristics.