Why Using Marine Lubricants is Important

Owning a boat is expensive. There are no shortage of jokes about how expensive boats are. Some people say the word “boat” is an acronym for “Bust Out Another Thousand” and this can certainly feel all too true. Between storage, fuel, maintenance, and other projects it never seems to end. That is one of the reasons that handier individuals will often do some, if not all of their own maintenance. There is nothing wrong with some Do It Yourself (DIY) mentality. Where some people make some mistakes is when they try to cut some corners or skimp on buying the right parts and materials. Throughout this post we will be elaborating on the importance of using marine grade parts and materials.

The Purpose of Oil and Other Lubrication on Boats and Engines

Oil within an engine serves four main purposes. Those purposes are to lubricate, protect, cool, and clean the engine. In order for the oil to work properly it needs to be the correct viscosity, or weight, which we go over some of the basics of later. Other forms of lubrication, like grease, are primarily used to lubricate and protect specific locations that wear and cannot be submerged or encased in oil. one of the most important areas to grease properly are the drive shaft splines on outboard engines. The comparable splines on sterndrives are the splines on the U-Joint that couples with the engine within the boat. It is important to use the appropriate grease which is capable of functioning under a load.

The Challenges of the Marine Environment

To understand why you need to use marine grade materials you need to understand that the marine environment, and marine engines are different. Some people think you can use automotive parts on boats. Generally this is a bad idea. Marine engines are exposed to a much harsher environment and running conditions than their automotive counterparts. That means marine engine parts are designed to handle these conditions, where automotive parts are not. For example, most automotive engines are not designed to run at 6000 rpm for extended periods of time, or to be run in close proximity to saltwater. Due to the harsh environment there are even some regulations on some parts which have mandates on being marine quality. These regulations get particularly specific on gas powered inboard or stern drive vessels. The regulations are in place to prevent explosions from occurring in the bilge of the vessel, but it is a great example of how bad a situation can get by using the wrong type of part.

What Makes Marine Lubricants Different

One of the most common pieces of maintenance boat owners decide to do themselves is the 100 hour service. As maintenance goes this is one of the simpler tasks. It is also where some boat owners make some expensive mistakes. People look at how expensive marine oils and lubricants are compared to automotive products and decide to just use automotive oils. There are several reasons that doing that is a bad idea. The biggest reason is water. Water is an inevitability for boats. Because of this marine lubricants are designed to absorb some amount of water and continue to lubricate. Automotive lubricants are not designed to do this, so if you use automotive oils for your boat a pocket of water will likely develop at the bottom of whatever reservoir the oil is being stored. That water will rust out whatever you want that oil to lubricate. This is the main reason it is critical to use marine lubricants for boats.

Understanding the Weight of Oils and Lubricants

Beyond that you need to use the proper weight oil per the manufacturer recommendations. There may be some variation based on ambient temperature of where you are operating your boat, but in general follow manufacturer specification for your specific engine model and year. Most modern marine engines require 10W-30 oil for the actual engine oil and 80 or 90 weight oil for the lower unit or drive. The weight of the oil is the viscosity rating of the oil at a given temperature. Two weight oils (like 10W-30) have a viscosity for colder temperatures and for when the oil is warm. It is a measure of how the oil will flow. Manufacturers, and their engineers, test and determine what they believe will allow their engines to perform the best for longevity, durability, and actual engine performance