There’s a lot of upsides to diesel fuel. More vehicular power, greater fuel economy, but one of the main downsides of diesel fuel is that it does not fair well in cold weather. When temperatures drop, diesel forms crystals that clog fuel fuel filters and fuel lines. Not only does this cause engines not to start, it can also lead to costly repairs if engines get damaged.
To prevent diesel fuel from gelling (or crystallizing) you should use an anti-gel fuel supplement. Anti-gel additives are easy to use – you just top off your fuel tank the treatment. Anti-gel additives drop the freezing point of diesel fuel so that it is less likely to freeze in cold temperatures. Anti-gel additives are designed to lower the Cold Filter Plugging Point (CFPP). The CFPP is the lowest temperature at which fuel will still flow through a specific filter.
The reason why we have to add an anti-gel additive to diesel is because diesel fuels contain wax. Normally the wax is a liquid in solution in the fuel. The problem with the wax is that this is what causes fuel to gel, and gelled fuel (or crystals) can block engine fuel filters. If the temperature is low enough then this will cause the engine to gel up completely and keep it from working at all. So why don’t we just remove the wax and skip the gelling issue all together? Well, the reason we have the wax component is because it gives fuel a good cetane value. Cetane offers power and better engine responsiveness. Wax content is lower in the winter but remains in diesel blends for cetane.
So when should you start adding anti-gel additives to your diesel?
1. When temperatures are below freezing (32°F)
It is always smart to start using anti-gel as soon as temperatures approach freezing. The rule of thumb is that the lower the temperature, the more fuel additive needs to be added. We suggest that you follow the instructions on the bottle of your anti-gel.
2. Rapid drops in temperature
If the weather man is anticipating a cold front, you are better off adding more anti-gel additive in preparation. Preparation is key. Anti-gel additives won’t damage your engine so when in doubt use extra.
3. When you add fuel
Use an anti-gel additive whenever you fill up at the pump in the winter. Most additives can be added before or after you add fuel. We like to add beforehand to ensure a good mixing.
4. When fuel begins to gel
Add an anti-gel additive as soon as possible. If your fuel is already gelled or your fuel lines are clogged up we recommend using an emergency additive that dethaws fuel and de-ices filters. These emergency treatments re-liquify fuel so that it can be combustible again.
For preventative measures, we at Fuel Ox™ provide a few anti-gel additives. We recommend using our Fuel Ox™ Cold Charge which prevents against fuel gelling. For already gelled fuel, we suggest using our emergency fuel treatment, Fuel Ox™ Heat Bomb, which is designed to restore the flow of frozen fuel lines.As with all of our products, a little bit goes a long way ; one ounce treats up to 80 gallons of fuel. You can find a complete list of our winter anti-gel additives below: