Brief Description: Engine Breather Tube Installation - Part 1
The Lycoming IO-390 had a breather vent on the accessory case near the top, left hand side. This opening vents crankcase gases and some "sludge" that can build up inside the engine. It is similar in function to a PVC valve on a modern automobile. The tube is directed down to the exhaust manifold where it is positioned exactly to allow the very slow, occasional drip of oily sludge to fall on the hot exhaust pipe causing it to burn up. This does seem like a better idea than running a long tube to the back of the aircraft to allow it to drip off the back of the plane.
Installation was pretty straightforward, although the physics of getting those particular two cushion clamps together such that a screw and nut could be added took nearly a hour and a *lot* of cussing... I'm just saying.
