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Diesel fuel freezes, difficult start of diesel engine at low ambient temperatures

Possible reasons:

  1. Application of diesel fuel not corresponding to the season or climatic zone, and also application of diesel fuel not corresponding to the performance standards (high content of paraffins). The reason for diesel fuel freezing is the presence of paraffin hydrocarbons (paraffins). At low temperatures paraffins begin to crystallize. As a result, diesel fuel thickens and gets viscous. The smallest crystals of paraffin clog the fuel filters, accumulate in pipe ducts and block fuel distribution to cylinders.
  2. Presence of moisture in diesel fuel. Moisture in diesel fuel can cause the failure of fuel distribution to the engine cylinders at low temperatures. At positive temperatures water and fuel form emulsion that destroys filter cartridges of the main filter, and at freezing temperature ice crystals clog the fuel filters.


  1. 1. In case diesel fuel, not corresponding to the season, climatic zone or performance standards is applied by necessity, it is recommended to introduce one of the special depressor agents into the diesel fuel before the decrease of ambient temperature:
    • Antigel + superconcentrate at the ratio of 1:1000 for diesel fuel
    • Antigel - superconcentrated diesel fuel treatment
    • Antigel – agent for improvement of low-temperature properties of diesel fuel
    Application of these agents according to the application instructions allows to decrease the diesel fuel pour point by 10…12 °С and cold filter plugging point by 8…10 °С.

    Note: It often happens, that summer diesel fuels are mixed with jet fuel, liquid petroleum oil or gasoline to decrease the pour point. It leads to the decrease of cetane rating of fuel and further breakdown of the engine and fuel pump. Besides such “winter solar oil” has a very low flash point, which increases the flammability of diesel fuel.
  2. For binding and removing moisture from diesel fuel regular application of one of the special cleaners for fuel systems of diesel engines is recommended:
    • Verylube fuel system cleaner (Diesel)
    • DIESEL-LUX – complex treatment
    • MultiCleaner (Diesel) - fuel system cleaner for diesel engine
    • F8 Complex Formula (Diesel) – diesel engine protection
    • - from the consequences of low-quality fuel application.


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