Hi Christian, I know this post is quite old, but I though I would answer in case anyone happens to search. There's no need to mess with the partitions, you can simply reformat the partition:
vmkfstools -C vfat -S vfatPrt1 /dev/disks/mpx.vmhba32:C0:T0:L0:8
You will end up with a new disk ID of course.
Then recreate the symlink to store if you need:
rm store
ln -s /vmfs/volumes/[new disk ID] store
No reboot required.