Electrolysis
Electrolysis is the most destructive corrosion to boats. Difference in the direct potential current that exists between two dissimilar metals is the reason for the problem. Stray current or circuit that is not following an anticipated path, improper wiring, poor choices in building materials, or defective electrical appliances can cause it. Introduced currents will flow by the path of least resistance.
Prevention:
Ø Don’t use automotive battery chargers on your boat. These chargers use an autotransformer in which the primary and secondary windings are electrically connected. Use only Marine battery chargers, which use an isolation transformer. An isolation transformer has separate windings and does not allow current to pass into the vessel from the utility connection
Ø Vessels using a positive ground electrical system should avoid mooring next to one with a negative ground system
Ø Check the connections to any two bilge pumps that are electrically connected. Ensure that each pump shares the same positive and ground connection. If one pump is grounded to the frame and the second is not, a stray current will be introduced
Ø Check your vessel for reversed polarity
Ø Check to see if any severe corrosion is present near telephone connections. Telephone service voltage can introduce 48 volts of current into the water
Ø Having sacrificial zincs installed on your boat and properly maintain them
Ø Keep a layer of quality bottom paint applied to all hull surfaces in contact with the water
Galvanic Corrosion
Galvanic corrosion occurs when two dissimilar metals form a natural battery when placed in contact with each other while immersed in seawater. Seawater is a perfect electrolyte for metals. Metals vary in their reaction to being part of this natural battery. Metals that are more active are anodes or less noble. In a galvanic cell, a less noble metal, like zinc, will dissolve sooner than a more noble metal such as brass.
Prevention:
Ø Use only protective bottom paint that is compatible with the materials on your vessels hull.
Ø Adequate zinc protection
Ø Steel boats should not be moored directly next to aluminum vessels Try to use fasteners on your boat made of similar metals throughout the vessel. Example: use all brass or all stainless steel
Sacrificial Anodes
Also known as Zinc, is used because it has a higher voltage in the water so the current will be more inclined to flow from it than from your propeller. Your hull could be under or over protected with zinc. It is vital that you have your zincs inspected at least once a month to assure proper protection.
Completing the electrical circuit:
Ø Properly install zincs to the items they are intended to protect. Example: bolted to the shaft or rudders.
Ø Assure Non-metal boats have copper bonding wire inside that connects all the underwater metal items together so they all share the protection from zinc anodes.
Ø Preventing other currents from entering this bonding circuit as they can easily overpower the small voltage available from your zincs and defeat the protection you need. You will notice it because your zincs get eaten up very quickly trying to keep up.
Isolation Transformers
Vessels moored along each other act like the plates within a battery. One boat can introduce current into the water and damage may not occur until it reaches a boat five slips away. Using an isolation transformer effectively takes you out of the battery and protects the boat from introduced stray current.
Double Check!
Ø Your marina should have a policy in place to address the proper use of shore power cords.
Ø Your shore power cords need to be designed for use in the marine environment and UL approved.
Ø Marine power plugs and receptacles are built to standards set by the National Fire Protection Association.
Ø Don’t use household extension cords, wrong plug in the wrong receptacle or use of a worn fixture because they could cause fire and corrosion problems!
Boat Bottom Paint
Bottom paints are formulated differently depending on the usage of the boat. Example: Boats that are raced, hauled and relaunched, spend considerable time sitting static, are used in warmer or colder waters etc all have bottom paints that are designed with those specific applications in mind.
Notice: different kinds of bottom paint have different compositions targeted at treating multiple types of fouling. It is wise to wait 90 days before hull cleaning a fresh bottom paint job.
Why choosing the best bottom paint for your boat is so important:
Ø Safety, Heavy fouling growth reduces the responsiveness of your craft and makes it sit lower in the water. This can have serious implications in challenging weather conditions.
Ø Protection, Prolonged fouling growth without cleaning will damage the substrate of the hull and cause potential costly repairs.
Ø Speed and Efficiency, As fouling causes drag, which slows you down and increases fuel costs.
Advantages of our service
Ø Regular hull cleaning service tailored to your hulls condition.
Ø Quality Control
Ø Detailed reports about your hull on every service.
Ø Free zinc installation
Ø Underwater surfaces will be ready for smooth boating
Ø A clean hull guarantees fuel savings.
Ø Competitive rates
Ø Intake, discharge and through hull fittings are ready for proper use.
Ø Top hull speed and R.P.M.'s whenever you are ready to go
Ø Your vessel's zincs will be inspected and replaced as needed.
Ø Regular hull servicing extends the time between haul-outs.
Ø You’ll have "peace of mind" knowing that your boat is properly maintained for optimum performance.
