The early prototype Twin Cam engines had considerable trouble with the oiling system.

The oiling system addresses the need to properly lubricate an engine when it's running.

These engines must be turned upright to produce the correct thrust line, thus requiring a new oiling system.

The two-stroke oil is ultimately burned along with the fuel as a total-loss oiling system.

The oiling system reveals the effort that was made to reduce the number of parts to a minimum.

Further improvements in later years included new pistons, rods, crankshaft, and an in-pan oiling system.

A total-loss oiling system is used on the car, lubricating 6 main oil-ways.

This last change was due to the different oiling system of the new engine, as described in the next paragraph.

The vital oiling system quickly picked up dust and debris, making the weapon unreliable in combat conditions.

Engine lubrication is via a dry-sump oiling system.