R60/5 Oil system question

[Micha]

While rebuilding the engine, we noticed that the oil pump is located above oil level, and is sucking the oil via a pipe that goes down into the sump. How is the pump taking oil up into the system while the pipe is empty and there's no vacuum? Let’s say after the engine stood still for a while (after standing a week, after rebuild…).
Thank you in advance,
Micha.

[schrader7032]

The pickup at the bottom of the sump should always be below the oil level. Under no circumstances should the oil system suck air. If it does and does it a lot, you'll ruin the engine.

If after a rebuild, it is probably wise to crank the engine but don't let it fire. One way to do this is to remove the float bowls so that no gas can be drawn in to the carbs to run. Remove the valve covers and crank until you see oil spurt out of the upper rocker studs. That will confirm that the oil pump has drawn in oil and gotten rid of the air.

After that, under normal operations, no air should get into the system as long as everything is assembled correctly and the oil level is maintained.