A new collection has been recently added to the New York records on FamilySearch.org
The New York Index to Alien Crewmen Who Were Discharged or Who Deserted, 1917-1957, contains indexes to alien crewmen who were discharged or who deserted at the Port of New York. The records may include the name of the crewman, age, vessel on which he served, date of discharge or desertion. This is a browsable collection, you cannot search on an individual name.
To access this collection, go to: https://familysearch.org/search/collection/2467808