[API-Problem | IWrenchable] Textures of my Block doesn´t change ingame

public short facing;	public short prevFacing;		public void writeToNBT(NBTTagCompound nbt) {				super.writeToNBT(nbt);				nbt.setShort("Facing", facing);	}		public void readFromNBT(NBTTagCompound nbt) {				super.readFromNBT(nbt);				if(nbt.hasKey("Facing")) {						prevFacing = facing = nbt.getShort("Facing");		}	}
	@Override	public boolean wrenchCanSetFacing(EntityPlayer entityPlayer, int side) {
		return side > 1 && facing != side;	}
	@Override	public short getFacing() {
		return facing;	}
	@Override	public void setFacing(short face) {
		facing = face;				prevFacing = face;				worldObj.markBlockForUpdate(xCoord, yCoord, zCoord);		worldObj.notifyBlockChange(xCoord, yCoord, zCoord, getBlockType());	}
	@Override	public boolean wrenchCanRemove(EntityPlayer entityPlayer) {		// TODO Auto-generated method stub		return false;	}
	@Override	public float getWrenchDropRate() {
		return 1F;	}
	@Override	public ItemStack getWrenchDrop(EntityPlayer entityPlayer) {
		return new ItemStack(getBlockType());	}