Read More Tag Doesn't Work?

Hello,

The read-more tag does not seem to function? I would like to break my large posts in to smaller pages for easy reading. This is the tag that wordpess uses, <!–more–> – and it shows in the text/visual editor on the post, but doesn’t do anything on the front page.

I dont mind sharing login info but I dont want to make it public.

Please let me know. Thanks. :D