Cylinder Oil Solution News

Castrol Marine said it has welcomed new guidance from Wärtsilä that undermines claims that mid-range base number (BN) oils represent a single cylinder oil solution for marine two-stroke engines. The advice confirms Castrol’s long-held concerns that using mid-range BN cylinder oils with higher sulphur fuels when slow steaming could lead to cold corrosion. The engine major has withdrawn approval for mid-range (50-60BN) cylinder oils when used with many marine engines running on Heavy Fuel Oil of above 2.5% sulphur content. New ‘letters of no objection’ to suppliers limit use of mid-range BN oils on all “Wärtsilä RTA, RT-fl ex and W-X engines as well as Sulzer two-stroke engines” to HFO whose sulphur content is “in the range 0.5<S<2.5 mass %”.

Drawing on OEM reports and its own engine performance tests, Castrol Marine has strengthened its conviction that optimum performance, when slow steaming, can only be achieved by having a range of cylinder oils available for the customer. content and low feed-rates. to those vessels regularly slow steaming, to ensure piston ring packs and liners remain in excellent condition. “The idea of a single, mid range cylinder oil solution for all vessels as sulphur limits are reduced may be seductive…