Corrosion Inhibitors & Penetrating Lubricants

Corrosion Inhibitors and Penetrating Lubricants - Resources & Information

Corrosion inhibitors and penetrating lubricants are important for boats and outboard motors because they help protect against corrosion and provide lubrication for the mechanical parts of the vessel. They can help protect against corrosion and provide effective lubrication for the mechanical parts of the vessel, improving its performance and longevity.

PartsVu offers a complete selection of Corrosion Inhibitors & Penetrating Lubricants from OEM manufacturers and trusted aftermarket suppliers. Whether you need Yamashield Rust & Corrosion Protectant, Mercury Corrosion Guard, and more, PartsVu has what you need to get the job done. 

Need help servicing your boat and outboard engine? PartsVu regularly publishes helpful how-to guides and other valuable maintenance information to help boaters service their outboard engines, boats, trailers, and more. Browse the PartsVu Xchange, our outboard maintenance blog, for a wide range of relevant topics and review the FAQ section below, covering everything you need to know about maintaining your boat in confidence.

Corrosion Inhibitors & Penetrating Lubricants FAQ

Why are Corrosion Inhibitors & Penetrating Lubricants so important for boats and outboard motors?

Some specific benefits of using corrosion inhibitors and penetrating lubricants include:

• Corrosion protection: Corrosion inhibitors are substances that are added to lubricants or applied directly to metal surfaces to help protect against corrosion. They work by forming a barrier on the metal surface that prevents the infiltration of water and other corrosive elements. This is especially important in a marine environment, where saltwater spray and other corrosive elements can cause rapid deterioration of metal parts.
• Lubrication: Penetrating lubricants are liquids that are designed to penetrate into tight or hard-to-reach spaces and provide lubrication for mechanical parts. They are typically used to lubricate parts that are difficult to access or that may have become seized or rusted due to lack of lubrication. Penetrating lubricants can help reduce friction and wear, improve the performance of mechanical parts, and extend their lifespan.
• Ease of use: Both corrosion inhibitors and penetrating lubricants are typically easy to apply and can be applied using simple tools, such as a brush, cloth, shop rag, or spray can. This makes them convenient and user-friendly options for maintaining the mechanical parts of a boat or outboard motor.

Overall, corrosion inhibitors and penetrating lubricants are important products to have on hand for the maintenance and care of boats and outboard motors.

How do corrosion inhibitors work?

Corrosion inhibitors are chemical compounds that are added to a material or solution to reduce or prevent corrosion. They work by forming a protective layer on the surface of the metal that prevents corrosive substances from coming into contact with the metal.

There are several different types of corrosion inhibitors, and each corosion inhibitor works in a slightly different way. Some inhibitors work by forming a film on the surface of the metal that is resistant to corrosion. This film can be either anionic (negatively charged) or cationic (positively charged), and it can be either organic or inorganic.

Other inhibitors work by reacting with the corrosive substances in the environment to form a protective layer on the surface of the metal. This layer can be either a passivating layer, which is a layer of corrosion products that is resistant to further corrosion, or a sacrificial layer, which is a layer of a less reactive metal that is more prone to corrosion than the metal being protected.

Regardless of the mechanism of action, the goal of corrosion inhibitors is to prevent or reduce the corrosion of metals in a variety of environments. They are used in a wide range of applications, including coatings, lubricants, and cooling systems, to protect against corrosion and extend the life of metal components.

How do I store and maintain my boat battery?

First, safely disconnect the batteries by removing the negative terminal and then the positive terminal. Use plastic caps on the exposed fasteners to prevent electrocution when dealing with multiple batteries.

Next, with the terminals exposed, you want to ensure that the batteries are completely clean of any corrosion, which can damage a battery’s ability to hold a charge after storage. Corrosion on batteries can be brown, white, or blue/green and must be scraped away with a wire brush to expose the fresh metal. Once scraped, coat them in vaseline or WD40 to avoid corrosion. Apply terminal caps and secure the batteries in a dry space.

After the terminals, check all cables for any signs of wear or damage from use. Damage can include frayed wires, burned insulation, or even a burnt smell. It may require examining your entire electrical system for shorts if you discover this.

What's the difference between surface rust vs penetrating rust?

Surface rust is a type of corrosion that occurs on the surface of a metal. It is characterized by the formation of a thin, reddish-brown layer of iron oxide (rust) on the surface of the metal. Surface rust is often the result of exposure to oxygen and moisture, and it can occur on any type of metal, although it is most commonly associated with iron and steel.

Penetrating rust, also known as pitting corrosion, is a more severe form of corrosion that occurs when the rust penetrates deeper into the metal, creating small pits or holes in the surface. Pitting corrosion is often the result of galvanic corrosion, which occurs when two dissimilar metals are in contact with each other in the presence of an electrolyte, such as saltwater.

There are several key differences between surface rust and penetrating rust:

1. Depth of corrosion: Surface rust only affects the surface of the metal, while penetrating rust can go much deeper.
2. Appearance: Surface rust is usually a uniform, reddish-brown color and can be easily removed with a wire brush or sandpaper. Penetrating rust is often deeper and more widespread, and it can be difficult to remove.
3. Damage: Surface rust is generally not a major concern and can often be removed or prevented with proper maintenance. Penetrating rust, on the other hand, can cause significant structural damage to a metal component and may require more extensive repairs.
4. Prevention: Surface rust can be prevented through proper maintenance and the use of marine rust inhibitors. Penetrating rust is more difficult to prevent, but it can be minimized through the use of corrosion-resistant materials and proper design and construction techniques.

What do you need to repair a boat in rust?

There are several steps that you may need to take to repair a boat with rust:

1. Remove the rust: The first step in repairing a boat with rust is to remove as much of the rust as possible. This can be done with a wire brush, sandpaper, or a rust remover.
2. Treat the metal: Once the rust has been removed, it is important to treat the metal to prevent further rusting. This can be done with a rust converter, which converts the rust into a stable compound that can be painted over.
3. Fill in any holes or pits: If the rust has caused holes or pits in the metal, these will need to be filled in before painting. This can be done with a metal filler or putty.
4. Sand and prime the surface: Once the rust has been removed and the metal has been treated and repaired, the surface should be sanded smooth and then primed with a rust-inhibiting primer.
5. Paint the surface: After the primer has dried, the surface should be painted with a high-quality marine paint to protect against further rusting.
6. Perform regular maintenance: To prevent rust from reoccurring, it is important to perform regular maintenance on your boat, including cleaning and drying the surface after use and applying rust inhibitors for metal as needed.

It is generally best to consult a professional for more extensive rust repairs on a boat, as proper technique and materials are important to ensure the repair is long-lasting and effective.

Is winterizing my outboard engine important?

Properly winterizing your outboard engine is the best way to prevent damage during the offseason from both lack of use and cold winter temperatures — depending on where you live. It also helps you with a smooth start to the beginning of next season.

There are seven basic steps to a proper winterization of your outboard engine:

• Thoroughly flush your engine with fresh water
• Stabilize the entire fuel system with fuel stabilizers
• Fog your engine
• Change the spark plugs
• Change the lower unit gear lube
• Disconnect your lead acid batteries
• Cover your engine with a fitted outboard cover
• Secure your outboard with a motor lock

With your engine properly winterized, there shouldn’t be any harmful debris or materials in the engine components that can cause damage over the off-season months. Plus, with new spark plugs, oil, and fluids, your outboard should start up right away when boating season starts in the spring or Summer.

For a more in-depth look at how to winterize your outboard engine, take a look at the following articles from the PartsVu Xchange. 

• Winterizing Mercury Outboard Motor—Mercury Marine Essential Maintenance
• Winterizing Outboard Motor—Yamaha Essential Maintenance
• Boat Winterization in South Texas?
• How to Winterize a MerCruiser Sterndrive

And of course, you can find all the winterization products you need at PartsVu.com to simplify the process!

Oxidation vs rust - what’s the difference?

“Is corrosion rust?” is a common question you’ll hear among even the most experienced of boaters. There’s some difference when comparing rust vs corrosion, so let’s clarify what the terms “rust” and “corrosion” actually are:

Rust is the name given to iron oxide (Fe²O³), a typically reddish-brown oxide formed by the reaction of oxygen and iron in the catalytic presence of air moisture, or water. Rust occurs in ferrous metals, with iron as part of its composition.

For most boats, iron-containing (ferrous) metals are used for their strength and relative lightweight. However, the proximity to water and humidity eventually corrodes these materials for boats and trailers over time, requiring preventative measures and replacement to keep them seaworthy.

Corrosion, on the other hand, refers to the process of metals being chemically destroyed or worn down by chemical reactions. Rust is a type of corrosion, but it is not the only type of corrosion that affects boats and boat trailers.

Several types of corrosion commonly occur in boats and trailers. As you examine your boat for signs of corrosion, try to identify which kind of corrosion is happening to help you troubleshoot where it’s coming from and how to prevent it.

Atmospheric Corrosion

When metal is exposed to the air that contains moisture and salt

Immersion Corrosion

Metal in water accelerates the corrosion process – especially in warm saltwater.

Galvanic Corrosion

This type of corrosion occurs when dissimilar metals are immersed in a conductive solution (water, saltwater) and are electrically connected. The metal that is more resistant to corrosion (the noble metal) “steals” mass from the other metals (less noble). Mass transfer occurs in the electrolyte (water) – which explains the purpose of sacrificial anodes in outboard and sterndrive motors.

Pitting Corrosion

Pitting corrosion is a localized form where tiny holes and cavities are produced in metals. Because these holes start small when they first occur, this corrosion can be difficult to detect on boats and trailers.

Poultice Corrosion

Poultice corrosion occurs when a metal is covered by absorbent materials, dirt, and debris, trapping moisture against the unprotected metal surface. This is most commonly seen with painted aluminum with water trapped under the paint or butted up against plywood, such as an aluminum fuel tank.

Erosion Corrosion

The constant velocity of moving water gradually wears away the metal. A boat’s trim tab is most likely to experience erosion corrosion.

Stress Corrosion

Hairline cracks can form for metal fittings that have been formed through bending or metal working, eventually branching out from the main crack. As the material weakens through corrosion, these branches – resembling a tree without leaves – spread further and further until eventually breaking under load or pressure.

Where can I learn how to prevent corrosion on my boat and outboard motor?

PartsVu has plenty of resources for everything you need to know about preventing how to avoid corrosion for your boat and all models of outboard motors. Start with the following guides and be sure to use the search bar to find plenty of other useful guides to maintain your boat in confidence:

• Marine Corrosion – Corrosion Types and What to Do About Them
• Yamaha Corrosion Prevention – Protect Your Engine
• How to Stop Marine Rust & Corrosion
• Yamaha Corrosion Prevention – Protect Your Engine