What are the three types of lubrication?

The engine lubrication system mainly employs three lubrication methods: pressure lubrication, splash lubrication, and periodic lubrication. Pressure lubrication delivers lubricating oil under high pressure to high-load components such as main bearings and connecting rod bearings via an oil pump, forming a stable oil film to ensure reliable lubrication. This is the primary lubrication method in modern engines. Splash lubrication relies on oil droplets splashed by the rotating crankshaft or oil ejected from the spray holes on the big end of the connecting rod to lubricate parts like cylinder walls and piston pins. Periodic lubrication involves manual grease application and is suitable for low-speed, dispersed components such as generator bearings, requiring maintenance according to the service cycle. Notably, most engines utilize a combined lubrication strategy. This hybrid design balances reliability and cost. The effectiveness of the lubrication system directly impacts the engine's lifespan. It is best to periodically replace the engine oil and filter that comply with the manufacturer's specifications. For example, fully synthetic engine oil meeting API SN or ACEA C3 standards offers better performance under high-temperature and high-load conditions.