What Happens to My PageRank If I Delete My Blog?

I have a second blog. I want to completely change what I write about on that blog. I want to keep the url and even where it is hosted. Question: If I were to delete all the catagories and posts that are now on that blog but kept the url, name, and host would I lose the page rank that it now has?

Remember that a while ago we had a Q&A about Google PageRank. There we explained that the three main factors that contribute to your PageRank are:

1. number of backlinks
2. quality of backlinks
3. relevancy of backlinks

If you were to delete all your posts, categories and site pages, and start from scratch, yes you would lose most of your PageRank. The backlinks would still be in place, but they would be pointing to non existent pages and would therefore report 404 errors, so Google would consider them as broken links.
Notice that I said “most” of your PageRank, though, because there is a possibility that part of it would remain. How come? Because I assume that your site would have a good amount of backlinks that point to its root domain (the homepage), and those would still count as backlinks. If you change the topic of the site they would lose some relevancy, but they would still be there.
One possibility that you could consider is to leave that current site as it is, and get a new domain to start your new blog. This would be indicated especially if you have some organic traffic flowing. You could place some ads there and let the money come in while you shift your attention to the new project.