Shell Mysella S5 S 40
Shell Mysella S5 S 40 is a premium stationary gas engine oil specifically developed for use in four-stroke spark-ignition gas engines operating on non-natural or “sour” gases such as biogas, sewage gas and landfill gas. These fuels can contain corrosive contaminants that place severe stress on engine lubricants. Shell Mysella S5 S 40 is formulated with high-quality base oils and advanced additive technology to provide excellent protection, extended oil life and reliable engine performance under these demanding operating conditions.
A key advantage of Shell Mysella S5 S 40 is its ability to deliver extended oil drain intervals in engines operating on sour gases. Such fuels often contain compounds that can generate corrosive acids during combustion, including sulphuric and halogenic acids. The lubricant is formulated with strong base additives and enhanced oxidation and nitration resistance, helping to neutralise acidic by-products and maintain lubricant stability over longer operating periods. This resistance to chemical degradation helps prolong oil life and supports improved maintenance intervals compared with conventional gas engine oils.
Shell Mysella S5 S 40 also provides excellent engine protection through its advanced additive system and carefully balanced low-ash formulation. Gas engines can be sensitive to deposit formation in combustion chambers, valves and spark plugs, which can negatively affect engine performance and reliability. The low ash content helps minimise the contribution of lubricant ash to combustion chamber deposits while maintaining strong anti-wear performance. This helps protect key engine components and supports cleaner engine operation over extended service periods.
Another important benefit of Shell Mysella S5 S 40 is its compatibility with engines equipped with emission control catalysts. The formulation is designed to work effectively in engines that use catalysts to control emissions of carbon monoxide, nitrogen oxides and formaldehyde. Maintaining compatibility with these systems ensures that the lubricant does not compromise emissions performance while continuing to provide reliable lubrication and engine protection.
Shell Mysella S5 S 40 also contributes to improved system efficiency in gas engine installations. In engines that utilise crankcase gas recirculation systems, the lubricant can help reduce fouling and clogging of charge air coolers. This helps maintain efficient heat transfer and airflow, supporting consistent engine performance and operational efficiency over time.
The oil is suitable for all types of four-stroke gas engines operating on sour gas fuels including biogas, sewage gas and landfill gas. It is widely used in energy recovery plants, waste-to-energy facilities and industrial gas engine installations where engines operate continuously and require reliable long-life lubrication.
Physical characteristics include a kinematic viscosity of approximately 125 mm²/s at 40°C and 13.5 mm²/s at 100°C with a density of approximately 890 kg/m³ at 15°C. The lubricant has a flash point of approximately 268°C and a pour point of approximately –18°C, providing dependable lubrication performance across a range of stationary gas engine operating environments.
