W3 Browser Caching and Pingdom Tools

Hey!

I’ve installed W3TC and Cloudflare on my blog this morning, but approx. 4 hours later I’m still receiving that there’s no browser caching being done when I test my website at tools.pingdom.com

And it’s not only external sites like google adsense, because that would be tolerable. It’s my own images and links.

How long does this take to kick in? Or how do I solve it?