/*
object_id    create_date    StringDate
14675150    2017-06-08 11:46:34.517    2017-06-08 11:46:34
16771167    2017-08-10 14:12:29.613    2017-08-10 14:12:29
33435193    2016-12-13 15:05:33.830    2016-12-13 15:05:33
38291196    2016-10-14 00:00:00.000    2016-10-14
56387270    2016-11-15 14:31:42.447    2016-11-15 14:31:42
71671303    2016-08-03 00:00:00.000    2016-08-03
*/
DECLARE @SampleData TABLE([object_id] int,[create_date] datetime)

INSERT INTO @SampleData
SELECT '14675150','2017-06-08 11:46:34.517' UNION ALL
SELECT '16771167','2017-08-10 14:12:29.613' UNION ALL
SELECT '33435193','2016-12-13 15:05:33.830' UNION ALL
SELECT '38291196','2016-10-14 00:00:00.00' UNION ALL
SELECT '56387270','2016-11-15 14:31:42.447' UNION ALL
SELECT '71671303','2016-08-03 00:00:00.00' 

SELECT *,
CASE 
  WHEN [create_date] = CONVERT(date,[create_date]) THEN CONVERT(varchar(10),[create_date],120)
  ELSE CONVERT(varchar(30),[create_date],120)
  END AS StringDate

 FROM @SampleData

SELECT [create_date],
    LEFT( CONVERT( varchar(24), [create_date], 121), 
      CASE WHEN [create_date] = DATEADD(dd, DATEDIFF(dd, 0, [create_date]), 0)
        THEN 10
        ELSE 23
      END),
    REPLACE( CONVERT( varchar(24), [create_date], 121), '00:00:00.000', '')
FROM @SampleData;

SELECT [create_date],
  LEFT( CONVERT( varchar(24), [create_date], 121), 
  CASE WHEN [create_date] = DATEADD(dd, DATEDIFF(dd, 0, [create_date]), 0)
    THEN 10
    ELSE 23
  END)