How Negative Temperatures Affect Diesel Engines

Every winter, truck drivers and truck fleets need to prepare their tractors and trailers for the cold weather to come. Winterizing your vehicles is vital in their longevity, and will save you thousands in repairs. While every season has its own weather, winter is by far one of the most trying times in the year in terms of maintenance upkeep. A truck driver should be conscious of every part of their truck and trailer that could be affected by changing temperatures, but one of the most common and costly things to care for is the engine itself. It's a common misconception that negative wind chill is what affects diesel engines, but it is actually just static air. The colder air temperatures without any wind chill will affect the diesel's performance. That combined with added wind chill can cause even worse problems.

Diesel's freezing point in -112 F, which would be an extreme weather condition, but that doesn't mean you won't start seeing issues with regular low temperatures as well. Because of diesel's contents, its consistency can change and will start to gel at temperatures of 15 F and below. Gelling usually occurs in #2 diesel fuel which has a higher viscosity than #1 Diesel, allowing the paraffin inside the diesel to crystalize. Also take into consideration that diesel can be contaminated, which means that microbial bacteria and fungi that can thrive off of the water and hydrocarbons sometimes found in diesel fuel. Although diesel is supposed to be pure from any contaminants, handling and condensation can leave water particles trapped in your fuel tank. Water's freezing point is 32 F, so when weather reaches temperatures below that, there is more likelihood that gelling will occur. Most service stations and gas stations offer a premium diesel mix that's blended to withstand colder temperatures and reduce gelling in colder climate regions, but even with the correct fuel, gelling can still occur in extreme circumstances.

Switch out Fuel Filters often

An indicator that gelling has already started taking place is having a full fuel filter. When you look at your fuel filter, the liquid should be less than half full. If your filter is looking more than half to three-quarters full, or has a cloudy appearance, that's an indicator that gelling is starting to occur. LGT mechanic's recommend that you should change out your fuel filter every oil change, and it's never a bad idea to keep extra in your truck if you'll be travelling through cold weather.

Running Additives

Winterizing for colder temperatures is something that every truck driver should be doing, and that requires regular maintenance. The correct diesel was mentioned above, but sometimes that still might not be enough to prevent gelling. Leftover #2 diesel from previous stops can mix with the newly added #1 diesel, which lowers the effectiveness of the lower-viscosity fuel.

A good practice to reduce gelling is running additives to your fuel tank. Diesel additives lowers the gel's temperature and adds lubricity to protect the fuel pump. Even if your fuel system is completely gelled, pouring anti-gel through it will loosen the mixture, giving you enough time to make it to a service station. What LGT recommends for our drivers is Power Service anti-gel and Howes.

Sometimes gelling is inevitable, but there are ways to fight it. Prepare your trucks and trailers for colder weather before it's here: pick up spare filters, switch out your fuel, and have anti-gel products with you if you'll be in colder regions.