Loss of smell. had x-rays done and drained fluid from ears. smell comes back at random times. but most of the time can't smell. what's wrong?

Tough situation: Smell is a very difficult sense to figure out sometimes. The fact that you can smell intermittently suggests that he neurologic connections are still present. Something is impeding smell. It could be related to sinusitis, allergies, deviated septum, turbinate enlargement, or nasal polyps. You should have a nasal endoscopic exam and imaging of brain and sinuses to help figure this out.