The liquid loader is a block from railcraft that loads liquids onto minecart tanks. There is also a Liquid Unloader. Its operation is practically the same as of the Item Loader, simply place above the track and it will load any liquid from adjacent tanks into any tank cart beneath it. Once finished, either when the minecart is full or there are no more liquids to load, it will send a redstone signal. It is recommended to use a boarding track beneath the loader, as it will automatically stop empty carts, load them and send them off again once finished by the redstone signal.