Since I have multiple partitions (some for Linux and some for Mac OS) I can't enable File Vault. It somehow complains that it can't do the encryption, given that there are other partitions.
Now what I thought about is reformatting the MacOS (Journaled) partition to Mac OS (Journaled, Encrypted) and then reload the image via TimeMachine. However, I'm not sure whether this will work (since File Vault doesn't work, and whether it's possible to load a unencrypted Time Machine Backup onto an encrypted partition) and how the boot process will look like (to get into the encrypted drive).
Do you have any suggestions for a guide that will show how this will work? Is there a difference between enabling FileVault and just changing the partition format on a hard-drive? Also, is there a difference in performance between the two methods?