Mbe 4000 blow air and oil out of blow-by tube. 255000 miles on engine.
Make: western star
Engine: mbe4000 450hp
Hello and welcome to Just Answer! I would be more than happy to assist you today.Excessive blow by can be caused by a failed turbo, failed air compressor, internal cylinder damage from ring worn. You would have to isolate the turbo and check. than isolate the air compressor and check if there is still excessive blow by suspect internal engine damage. Also check your oil level and make sure it is not over full.
16 Years working on Cummins Diesel engines,