PLATE-WEAR 3745278 - Caterpillar

Caterpillar EnginesWhen an engine is not used for a long period of time, oil can run off the cylinder walls, piston rings, main bearings, connecting rod bearings, crankshaft, gears and other parts that normally get lubrication. This loss of lubrication permits corrosion to start on the metal surfaces, especially in areas of high humidity (water in the air). When the engine is started again, before these surfaces get oil, there will be metal to metal contact which will cause wear.
Special Instruction, SEHS7392, gives procedures and recommendations that will keep the possibility of damage at a minimum when an engine is started after storage.