Thank you for posting your request on History Hub!
If you have not already done so, we suggest that you request a copy of his Official Military Personnel File (OMPF). OMPFs and medical records of enlisted men of the U.S. Navy who were separated from the service after 1885 and prior to 1958 are located at NARA's National Personnel Records Center (NPRC), (Military Personnel Records), 1 Archives Drive, St. Louis, MO 63138-1002. To request these records, please mail a completed GSA Standard Form 180 to NPRC. Veterans and their next of kin also may use eVetRecs to request records. See eVetRecs Help for instructions. For more information see Official Military Personnel Files (OMPF), Archival Records Requests.
Due to the COVID-19 pandemic and pursuant to guidance received from the Office of Management and Budget (OMB), NARA has adjusted its normal operations to balance the need of completing its mission-critical work while also adhering to the recommended social distancing for the safety of NARA staff. As a result of this re-prioritization of activities, you may experience a delay in receiving an initial acknowledgement as well as a substantive response to your reference request from RDT2. Also, the NPRC is currently only servicing emergency requests associated with medical treatments, burials, homeless veterans, VA Home loan guarantees, and employment opportunities. If this is urgent, please see Emergency Requests and Deadlines. We apologize for any inconvenience.
In the meantime, there are quite a few military records available on Ancestry. Ancestry is a paid subscription site but can be accessed for free through most public libraries. Also, if you provide more detailed information about what military branch he served in we can point you to more specific National Archive records.
We hope this is helpful. Best of luck with your research!