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Winter Diesels

In Australia the specification for diesel varies seasonally. In winter, fuel manufacturers are required to produce diesel where the temperature at which wax crystals
begin to form is lowered. From time to time and in certain locations, the Cloud Point determined in the Australian Standard may not be low enough to protect the diesel from waxing up.

Our Highland and Alpine diesel products not only conform to these requirements but are formulated to have lower cloud points.

All diesel fuels contain wax molecules. These are natural components of the crude oil that diesel is produced from.

Wax is considered an important diesel component because of its high cetane value (for good ignition quality of the fuel).

However, in severe winter conditions especially in inland or high country areas, the diesel may get cold enough for the wax to start to crystallise (solidify).

If enough wax crystals solidify, the fuel lines, filters and strainers in diesel powered engines and machinery may become blocked and as a result may become difficult or impossible to start and operate.

This phenomenon is known as “waxing”.

Emergency procedure for cold start

Should wax crystals cause a problem, then the following emergency start up procedure has been taken from Australian Standard AS 3570-1998.

Check dipstick to ensure engine oil is fluid. If the engine oil is fluid, go to step 2. If it is not fluid do not attempt to start the engine because waxy fuel in the crankcase has frozen. Wait until the oil becomes fluid. Using external heat source such as a blow heater, steam line or exhaust gases from another vehicle will speed up the process. Once the oil is liquid then replace it with fresh oil in accordance with manufacturer’s instructions.

Attempt to start the engine. If the engine fails to start then check the fuel filter for wax. If the fuel won’t flow or is hazy then the filter body and fuel lines will need to be heated using a blow heater or steam cleaner. Once the engine starts, run it at low speed until it is warm. This will prevent further blockages.

Rev the engine violently after starting. This could damage the injection pump and bearings.

Light a fire under the vehicle fuel tank or around equipment.

Add petrol to diesel fuel. Petrol has a low flash point, viscosity and cetane, and the resulting blend may result in increased fuel system wear and operational problems.

Ampol Winter Diesel blends are specially formulated diesel products with lower cloud points compared to regular diesel. They are formulated to our strict quality standards to inhibit waxing and crystal formation.

Ampol conducts regular testing of our winter diesels for quality assurance purposes, providing our customers with quality and peace of mind.