encumber vs put a monkey wrench in the works of

encumber

verb
  • To burden with a legal claim or other obligation. 

  • To load down something with a burden. 

  • To restrict or block something with a hindrance or impediment. 

put a monkey wrench in the works of

How often have the words encumber and put a monkey wrench in the works of occurred in a corpus of books? (source: Google Ngram Viewer )