Mobil Pegasus 705
Mobil Pegasus 705 is a high performance mineral gas engine oil formulated to lubricate a wide range of natural gas-fuelled engines, including lean-burn, high-speed designs that are sensitive to valve recession. It is an SAE 40 intermediate ash lubricant developed to meet the lubrication requirements of severe turbocharged, higher-speed four-cycle gas engines operating on clean fuel gas with low levels of hydrogen sulphide.
Mobil Pegasus 705 provides excellent protection for valve guide faces and seats, helping reduce valve recession in lean-burn gas engines. The formulation also delivers strong protection against piston scuffing, scoring and cylinder liner wear, supporting longer engine life and improved reliability. These characteristics make the oil particularly suitable for engines operating under high load and continuous duty conditions.
The product is designed to promote improved engine cleanliness. Its balanced additive system helps minimise ash deposits in lean-burn and low-oil consumption gas engines while maintaining strong resistance to oxidation and nitration. This helps reduce sludge and deposit formation, supporting cleaner operation and extended service intervals.
Mobil Pegasus 705 also offers excellent resistance to foaming and strong corrosion protection. The formulation provides good Total Base Number retention, helping control acids formed during combustion and protect internal components. This contributes to improved operational reliability and reduced maintenance requirements.
Mobil Pegasus 705 is recommended for use in both medium- and high-speed gas engines operating on natural gas. It is suitable for applications requiring an intermediate ash SAE 40 lubricant with good valve protection, deposit control and wear performance in lean-burn engine designs.
Physical characteristics include a kinematic viscosity of approximately 126.2 mm²/s at 40°C and 13.2 mm²/s at 100°C, with a viscosity index of around 98. Mobil Pegasus 705 has a flash point of approximately 252°C, a pour point of approximately −18°C, a Total Base Number of 5.6 mg KOH/g and sulphated ash of 0.5%, supporting reliable performance in gas engine applications.
