Thank you for your post.
I copied your example, pasted it into a Text Editor, and saved the file as Test.csv. I launched FileMaker Pro 10 and created a database file with a Number field, Time field, Date field, and two text fields. I imported the Test.csv file and all the data came across correctly. I imported the same file a second time. I created a Summary field that was a total of the Time field, and the result was 17:12:00.
I don't know why it isn't working for you, and I know that doesn't help you. Since your CSV file probably doesn't just have one record, I would like to try the import using your CSV file. I have sent you a private message (top of this screen - right side - X Messages) with instructions where to send the CSV file.