348 What are these?

Bleed the cooling system. The WSM covers it btw.

 

Bleeder valve (screw actually) for radiators. Word to the wise, easy to drop and not so easy to replace.

 

WSM = WorkShop Manual

 

Daniel,

Have you visited www.my348.com?

 

When doing an engine out, they use these bleeder valves to refill the cooling system. No need for you to worry about them under normal conditions.

 

Use an Airlift system and you never have to ever use those bleed screws at all.