Need to remove files

My external HD for my Time Machine back-up crashed due to a corrupt file in the backup, I want to remove some files on the external backup Time Machine file in order to copy the clean file to a new external HD. How do I remove a file(s) from Time Machine Back-up

Macbook Pro 17-inch Early 2011, 2.2 GHz Intel Core i7, 16GB 1333 MHz DDR3, OS X Yosemite, Version 10.10.3