The Ultimate Guide to Keeping Your Aluminum Boat From Deteriorating

How To Stop Electrolysis On Aluminum Boats, And Fight Against Deterioration

Aluminum as a material for boats has a lot going for it. It’s lightweight, which is a significant advantage if you have to haul it. It can stand up to a lot of punishment on the water. And you can fix it easily if things go awry. But it’s not a cut-and-dry solution. That’s one reason why you may wonder how to stop electrolysis on aluminum boats?

What Is Electrolysis?

The term, electrolysis, is a misnomer. It’s not an accurate description of what’s happening to your boat. That term describes the process involves the movement of current between positive and negative electrodes.

What’s occurring is chemical but focuses more on the reaction between different materials present on the craft and the environment. It’s something that is of particular concern in vessels in seawater but still has implications for freshwater. It boils down to how the chemicals react since many carry an electrical charge that facilitates the action.

Oxidation vs. Corrosion

Chemicals consist of atoms with positive (proton), negative (electron), and neutrally charged particles (neutron). Oxidation occurs when releases electrons to another substance. Conversely, reduction reactions involve the acceptance of those particles. Redox describes the combination of the two, which reflects its balance of charges.

Corrosion is one form of this process that applies specifically to metals like aluminum and some other materials. Oxidation can occur on any substance with or without oxygen present, despite the implications of the term. The former is typically a destructive reaction that is irreversible. The latter is sometimes desirable in laboratory settings to create other compounds.

The form of these reactions that is of concern is rusting. It can happen on any vessel whether it’s a johnboat or personal watercraft or even your power boat. The correct term is galvanic corrosion.

The aluminum is giving up electrons and, in turn, weakening its structure starting at the molecular level. While it may sound odd, the process is creating a chemical balance between the metal and its environment, the water.

It’s more likely to happen in saltwater because of the ubiquitous presence of the charged atoms of sodium and chloride. The charged particles or ions dissolve, making it an electrolyte solution. That, along with other metals that are in contact with your boat create the perfect storm for corrosion to occur.

These chemicals exist to varying degrees in brackish and freshwater too, making an aluminum boat kept on the water vulnerable as well. And of course, the presence of oxygen makes it possible. The fact that the metal is chemically active seals the deal.

Types of Corrosion

Corrosion can occur in other situations that may or may not apply to aluminum boats. For example, high temperatures can also spur this reaction in engines due to the other present chemicals. Bacteria are another culprit that can attack materials ranging from cast iron to plastics. Wherever charged atoms and molecules are around, the possibility exists.

Preventing Galvanic Corrosion

But the critical question is how to stop electrolysis on aluminum boats? Prevention, of course, is the wisest course of action so that you don’t have to start researching new boat prices. The quickest ways to prevent deterioration of your boat are also the easiest. Bottom paint will provide a barrier to the chemical reactions causing galvanic corrosion.

You needn’t apply it any farther than the waterline along the sides. You can paint the rest if you’d like, but it isn’t necessary. And it may surprise you to learn that keeping the bare metal is better for it. Since aluminum is chemically active, it’s staying busy in the presence of oxygen in the air to form aluminum oxide which also protects it from corrosion.

You also have to keep the inside of the boat dry. If water is there, the chemical reaction can occur and start to eat away at your craft. Then, you’ll be breaking out that boat payment calculator.

Setting Up a Scapegoat

Another solution is to direct the chemical activity elsewhere to a so-called scapegoat or sacrificial anode. It is a piece of metal composed of either magnesium, zinc, or aluminum that you attach to the bottom of the craft. They work by taking one for the team or the boat, as it were. They are more chemically active or noble and will give up their electrons instead.

You can use magnesium for boats on freshwater only since it’ll dissolve too quickly if there is salt in the water. Aluminum is an excellent choice for brackish or saltwater. Zinc is the metal of choice for the latter. You can also place anodes on your engine so that you don’t have to shop used outboard motors for a new one.

You should plan on using several small ones placed all along the bottom. The amount you need depends upon the chemical activity of the environment and your boat. Ideally, they will last the entire boating season to about half their original size. If not, adjust the amount accordingly because too many can present issues too. Also, make sure to get ones that are military spec Mil-A-18001J.

Leave the anodes bare and ensure that they are firmly in place. You will have to replace them the next season, but that’s not a bad thing. You’ll know that they’ve done their job and protected your boat.

Other Things You Can Do

There are more precautions you can take that can also keep your craft intact. First, stick with products made for use with aluminum. That includes paint, lubricants, grease, or any other material you’d apply to it. It may be hard to get your head around the chemistry part, but having a boat of this material calls for different care than one made of fiberglass.

With that in mind, you should also keep on top of any damage to the bottom paint like chips or scratches. Those bare spots are kryptonite to your boat. If it’s on saltwater, put it on a lift when you’re not using it, if possible. Hose it down thoroughly to get rid of the salt that could start to erode it. Make sure only to use freshwater and dry it off afterward.

If your boat is at a marina and you have shore power, hook it up to an isolation transformer when it’s at the dock. It will prolong the life of your anodes and, thus, prevent corrosion. Other vessels and personal watercraft can contribute to the chemically charged environment, making it a smart option.

Also, you should avoid contact with other metals. That includes bolts and other hardware. Placing nylon washers to keep the heads from touching the aluminum will help protect it. The same precaution applies to your fishing tackle. Keep lures and hooks off the bottom of it and out of the bilge. Contact with these items will also weaken the structure over time.

Aluminum boats offer a lot of advantages to boaters and anglers alike. However, these benefits belie the fact that you need to take extra precautions to protect it from the elements. Fortunately, there are several things you can do to prolong its life for years of boating pleasure.