Splash lubrication

Splash lubrication is an antique system whereby scoops on the big-ends of the connecting rods dip into the oil sump and splash the lubricant upwards towards the cylinders, creating an oil mist which settles into droplets.

The oil droplets then pass through drillings to the bearings and thereby lubricate the moving parts.

The splash lubrication system has simplicity, reliability, and cheapness within its virtues.

[4] However, splash lubrication can work only on very low-revving engines, as otherwise the sump oil would become a frothy mousse.

The Norwegian firm, Sabb Motor, produced a number of small marine diesel engines, mostly single-cylinder or twin-cylinder units, that used splash lubrication.

An early Sabb engine that would have used splash lubrication.
The centre con-rod has a spade for splash lubrication.