Air will be expelled from the lines and injectors in due course.
Any clearer??
Ok, that might work on some engines, but not all. Lets remember that aircraft injectors work on a negative pressure.... or a pressure diferential, and Diesel injectors use a positive pressure to lift the valve plate and release the pintle.
Hence the High pressure part of the injector pump that diesels have and aircraft don't have. If the air bubble in the injector line in most diesels is big enough, it will just sit in the line and compress and decompress all day without building enough pressure in the injector for it to crack off, and therfore must be bled out from just prior to the actual injector.
Oh, sorry guys.......thread drift.
