Q: When you cannot draw because there are zero cards in your Deck, can you instead add a "Iron Core of Koa'ki Meiru" to your hand?
A: If you have zero cards in your Deck, then during your Draw Phase you cannot draw, so you cannot activate the effect of "Iron Core of Koa'ki Meiru".
Original Source: http://yugioh.faq.konami.jp/EokpControl?&lang=en&tid=48784&event=FE0006
Translation by: http://yugioh.wikia.com/wiki/Card_Rulings:Iron_Core_of_Koa%27ki_Meiru
The same applies for Spirit Burner.