Technical Alerts

Fuel Specifications Alert for Construction Plant Diesel-powered Engines

This alert relays issues on fuel specifications for mobile and static plant powered by gas oil (red diesel) engines following feedback from owners and manufacturers. The alert advises owners and users of potential problems if the incorrect specification of fuel is used, particularly machines fitted with EU Stage V engines. This is because engines used in modern construction plant are becoming more sophisticated to reduce exhaust emissions and improve fuel consumption and can be a particular problem for engines designed to meet stage V emission requirements. It is therefore essential that plant owners and users are using the correct fuel for their machines, as specified by the plant manufacturer.

Some manufacturers have reported cases of fuel filters on later designed engines blocking where incorrect specification fuels are used and state that where filters are not changed, possible damage to the fuel and after treatment systems, especially on stage V engines, can occur with the results being potentially extremely expensive. To understand the problem, plant owners need to know that there are currently four specifications of diesel fuel commercially available in the UK and in 2011, it became a requirement that all fuel used in non-road mobile machinery (NRMM) must comply with EU Ultra Low Sulphur Diesel (ULSD) regulations and must therefore contain no more than 10mg of sulphur per kg of fuel. Since white road diesel (DERV) was already ULSD compliant at this time, it is often believed that the specifications for red diesel and white diesel have been identical since the regulation change. This however is not the case.

There are two recognized standards of red diesel (Gas Oil) that are currently in use: BS 2869 Class A and BS 2689 Class D. Class A2 has a maximum sulphur content of 10ppm and is used for excepted vehicles, while Class D has a maximum sulphur content of 1000 ppm and can only be used for heating or static generators. With plant manufacturers continuously improving the technologies used within plant diesel engines, plant owners and users are strongly advised to check that the fuel obtained or used by themselves or their customers complies with the plant manufacturer’s specification and contact the manufacturer if need be to check the fuel requirements for their machines.

If the incorrect specification fuel is used, it can and has resulted in costly engine breakdowns and recovery costs. There is also a possibility that a manufacturer’s warranty would be void. Where plant is on site for long periods or hired on a non-operated basis, it is essential that all plant users are made aware of the correct fuel specification by the plant owner, as the user or a designated person or persons will generally be responsible for refuelling the machine and that the information has cascaded down to all those involved.