Skip to content


The Importance of Oil & Coolant for a Diesel Generator

The Importance of Oil & Coolant for a Diesel Generator

Your Diesel generator works hard and hot, especially when used as a primary power solution. Therefore, multiple fluids are used by your Diesel engine for proper lubrication and cooling. These are your oils, lubricants and coolants. Ensuring your Diesel generator is using the top-quality lubricants it needs to run efficiently and safely is equally as important as finding genuine, branded parts. Learn more about the lubrication and cooling process of your Diesel generator in this article!


Diesel power is essentially the result of kinetic energy. An intricate set of moving parts are powered by combustion in order to create motion in the actuator. Whilst the main result of this is electricity, along the way energy is expended as heat. Overheating can cause your Diesel generator to derate and become inefficient, whilst friction (which creates said heat) is the main contributor to the general wear and tear of your Diesel generator. Therefore, oil is used to lubricate moving parts of the Diesel generator and reduce friction.


When two surfaces travel in motion whilst in contact, they rub against each other. This is known as friction. There are many ways to reduce friction. The simplest, of course, is to separate the distance between two parts, though this isn’t always possible. The other possible solution is to limit the surface area of contact points. The most effective way of doing this is through ball bearings. However, the overall greatest reductions in friction come by placing a viscous fluid between the two parts. This causes them to no longer contact, acting as almost a barrier against friction. Lubricant is this barrier for many key parts of your Diesel generator.


Coolant is a fairly simple concept. Diesel generators run hot. Energy cannot be created or destroyed, only converted. Unfortunately, no conversion system, be it a Diesel generator or otherwise, is 100% efficient. Energy lost in the conversion is expelled as heat. As we mentioned prior, overheating causes inefficiencies and potential safety risks. Therefore, we use coolant to reduce the overall temperature of a Diesel generator. This cooling solution is usually a mixture of soft water, glycol and other chemicals. Glycol also provides some anti-freeze protection, ensuring your Diesel generator isn’t subjected to cracking in low temperatures.

PowerMark offers a variety of lubricants and coolants from trust diesel generator manufacturers, including Perkins, Scania and Cummins. Alongside this, PowerMark is also home to the top-quality and affordable CPS blends. These lubricants are ideal for a vast array of sectors, including automotive and industrial

We hope this guide has shown you the importance of Diesel generator oil & coolants. Contact our team today if you'd like to discuss any options, or have any queries. 

Previous article How to: Upgrade Your Generator
Next article Diesel Generator Battery Safety Guide