Block to inlet breather pipe

[adamS]

During my unsucessful HG swap I came accross this pipe with a spring inside.

I'm curious what's its responsible for and how it works. Anyone know?

thanks

[chu346]

Crank case ventilation pipe, to let out all the gases that get built up.

[adamS]

The scavanger system? So the gases are them combusted?

cheers

[gcorky]

oil vapour /mist .did you renew o rings top and bottom?if not may cause idling/running issues?

[Brianmoooore]

It's not only a vent pipe. It's the pipe through which all the oil pumped to the cam and rockers gets back to the sump as well.