Oil Leak from the turbine seal

Oil Leak from turbine seal:

Obstructed turbo oil drain line - Remove obstruction or replace oil drain line

Obstructed engine crankcase vent - Clear obstruction

Turbo center housing sledged or coked - Change engine oil, filter, replace turbo as required

Worn engine rings or liners (blowby) - Repair as needed

Internal engine problem (valves, pistons) - Repair as needed

Dirt caked on compressor wheel - Clean with non caustic cleaner and soft brush, change filters

Damaged turbo - Analyze turbo to determine failure, replace turbo