Cold Weather and (Bio)-Diesel Fuel
As the temperature drops, the wax naturally found in diesel fuel begins to form
crystals. The point at which wax crystals form is known as the cloud point.
These wax crystals eventually clog the fuel filter and starve the engine of
fuel or prevent it from starting. While low-quality fuels may form wax crystals
in temperatures as warm as 40°F (4°C), most fuels have a cloud point near 32°F
(0°C).
Cold Weather Performance Parameters
There are several areas of diesel fuel improvement touted by various cold flow
additive manufacturers, including pour point, cloud point and cold filter
plugging point (CFPP). Many claims can be misleading, so it is important to
understand this terminology in order to determine which products truly provide
superior performance.
It is important to distinguish between CFPP and pour point.
Many competitive products make great claims regarding pour point, leading
consumers to believe their products are superior when they actually have an
inferior CFPP. Once fuel surpasses its cloud point, the wax crystals begin to
clog the fuel filter. The CFPP temperature is a more important characteristic
than pour point because the engine will not run if fuel cannot pass through the
fuel filter.