If you want to allow users to vote, but you don’t want them to see the overall rating, you can create a template that will help you achieve this. You can also download the template from this article.
The key to this is the template. The template attached to the end of this article and it does few things. Rating stars element is not displayed after the rating, and when it is displayed, the rating value is not shown. Only current user rating is displayed, but the overall rating is not displayed. Rating text is also not displayed under the stars.
To get more information about installing the template, check out this article: