Why Diesel Fuel Gels & How To Prevent It From Occurring – Maintenance Monthly

With colder temperatures, comes a greater risk for diesel fuel gelling, which can disrupt engine performance, cause costly repairs, and lead to downtime for vehicles. Understanding why gelling happens, when it occurs, and how to prevent it is essential to ensure reliable performance in cold temperatures. For this Maintenance Monthly, we will cover the key details about diesel fuel gelling and provide essential tips to help prevent it.

Why Does Diesel Fuel Gel?

Diesel fuel gelling happens when the paraffin wax naturally found in diesel solidifies as temperatures drop. At low temperatures, this wax begins to crystallize, forming clumps. When enough wax solidifies, this can block fuel filters and lines, preventing the engine from starting or running properly.

When Does Diesel Fuel Gelling Occur?

The specific temperature at which diesel fuel gels varies based on its makeup and quality. Typically, gelling occurs when temperatures consistently fall below 10°F to 15°F. The process can begin when temperatures are around 32°F, and for #2 diesel fuel, around 20°F, as the fuel reaches the cloud point, developing a cloudy appearance due to the crystallization of the wax. As temperatures continue to decrease, the fuel thickens and reaches the pour point, where it can no longer flow freely. Finally, when temperatures drop below 10°F to 15°F, the fuel fully solidifies, marking the gel point.

How to Prevent Diesel Fuel Gelling

Preventing diesel fuel gelling requires proactive measures. Below are a few preventative steps you can take to help protect your fuel system:

1. Regular Fuel Filter Replacement

Ensure your fuel filters are clean and replaced as recommended. A clogged filter can worsen the effects of gelling by further restricting fuel flow.

2. Consistent Fuel Purchase Locations

Stick to reliable fuel suppliers to ensure you are getting high-quality diesel, potentially treated or blended for cold weather performance.

3. Keep The Tank Full

Keeping your fuel tank full minimizes condensation, which can increase the risk of freezing in the fuel system and cause the fuel to thicken and gel

4. Maintain Fuel Heater Operation (If Applicable)

If your vehicle or equipment is equipped with a fuel heater, regularly check that it is functioning properly to help maintain optimal fuel temperatures.

5. Treat Fuel With An Additive

Use high-quality anti-gel additives designed to lower the Cold Filter Plugging Point (CFPP) of your diesel fuel, preventing the paraffin wax from crystallizing. Be sure to add these products to your fuel tank before temperatures drop.

Diesel fuel gelling can be a frequent challenge during the winter months, but it can be mitigated with the right preparation. By understanding what diesel fuel gelling is, why it happens, and how to prevent it, you can keep your trucks running smoothly even in freezing temperatures. Stay ahead of the cold and ensure your trucks are ready to perform in any weather. Interested in learning more? Connect with your local Kenworth of Pennsylvania store today.