Website header code decrease google can't crawl due to size. No Meta Description Appearing.

[Carl_Fisher]

Hi, 

Can any assist I have an issue with the meta description not appearing in google on the main pages of my website. 

Ive been informed that: The header of your page consists of 2,609,151 (2.6m) characters.  Your header is such an extreme length it’s unsurprising Google can’t find the meta title and description. It can’t see the wood for the trees! My best guess is that Google is trying to read the header, but getting so bogged down with unnecessary code that it just gives up.

Can anyone advise how this can be corrected with out causing any detriment to my website?