Here is how you do this (no ccleaner needed)
Go to google chromes menu (the three lines at the right end of the screen normally under the close button if you dont know) it looks like this:
Link Removed
go to "settings"
and then scroll down in the settings to "show advanced settings"
then click that
then under "privacy" go to "clear browser data"
This will not automatically clear your browser data, instead it gives you little tick boxes you can uncheck/check by clicking them.
uncheck all the boxes except for "Cached images and files"
this will single out your cache to be cleared and not anything else.
After doing that just hit "clear browsing data" and boom your cache is clean