custom RSS

Currently, my blog’s RSS feeds received through email shows my entire post. It doesn’t give readers much of a reason to visit my site. Can I change that? I’ve tried using excerpts but doesn’t change anything. Is this an RSS default or is there something I can do in the WP coding to change it so that RSS emails only give readers a blurb of the entire post so they have to click the link to read the whole thing?

My blog is http://www.simplerliving.ca

Thanks for any help.