If you are on VMFS5 then no block size will impact the disk size (which even on VMFS 3.x should be able to give you at minimum 255 GB vmdk on any blocksize). If you can not expand it to 61 GB now it should be something else.
Could you look through either the command line or through Storage Views and show all virtual machines files? And verify again that there are no hidden snapshots on this VM? Look for *delta*.vmdk.