Vessel operator Great Offshore was concerned about deposit buildup in the Rolls Royce L9P series engines of its supply vessel, Malaviya 25. Left unchecked, the situation could have led to premature component wear and an increase in maintenance and unscheduled downtime. Oil consumption was also high and drain intervals were decreasing.
ExxonMobil engineers proposed switching the vessel to Mobilgard 412 oil following an onboard inspection. The lubricant, part of the Mobilgard™ 12 Series oils, is for use in marine and industrial trunk piston engines operating on low sulphur distillate fuels.
Engineers observed improved cleanliness in engine components, with minimal deposits on the crankcase, main engine bearings, rocker arms and plungers. Malaviya 25 also reported improved engine equipment reliability, reduced maintenance costs and a decrease in unscheduled downtime.
By using Mobilgard 412 oil to lubricate its engines, Malaviya 25 was able to extend its drain interval period by almost 30 per cent, and its oil consumption decreased from 0.9 gms/kwh to 0.7 gms/kwh. The filter change interval improved by almost 28 per cent.
“The performance of Mobilgard 412 was found extremely satisfactory for the lubrication of Rolls Royce L9P series engines. The approximate savings by reduction of specific lube oil consumption, increasing oil drain intervals and other consumables has given us immense benefit of close to $32,000 annually,” said P. Lakshman, Technical Deputy General Manager at Great Offshore.