All the installation instructions are made by the manufacturer and only the manufacturer decided to include or not such instructions with a part.
Originally Posted by nancytp2000
...WHAT GOOD IS A PART IF YOU DON'T SEND A SCHEMATIC OR INSTRUCTIONS WITH IT?...
Shut off the water to the refrigerator. Disconnect the incoming water line from the water inlet valve. Remove the plastic tubes from the water inlet valve by pushing in the center collar while pulling out the tube.
Install the new water inlet valve in the reversed order.
Here are the breakdown diagrams and Replacement parts for MAYTAG MSD2351HEB Ref - SXS/I&W | AppliancePartsPros.com