Note: This issue was addressed in ArcGIS 10.3.1.
Displaying image services that are published from a mosaic dataset with a vector field data type may freeze, if the service is large and uncompressed.
A mosaic dataset created from a multidimensional raster type (netCDF, GRIB, or HDF) is 64-bit by default. If it is not compressed, the image request size exceeds the ArcSOC heap size setting.
Set the compression format when publishing the image service.