I bought a Travel Trailer in June and basically everything with the water system was just nasty.  Since at the time I was going away in 1 week without water hook ups I sanitized the holding tank and replaced the water fill hose, over flow hose, drain hose and drain.  Sorry, no pics 'cause I was in a hurry then.  I haven't thought of the city water hook ups because I haven't been to a campground that had water so I just used my holding tank. 

Fast Forward to my trip next week and I have water hook ups!!!! crap, now I need to replace the water inlet.  I don't even want to flush the toilet with the water that runs through this rusty thing.

[IMG]http://i1357.photobucket.com/albums/q752/CamperDude/water%20inlet_zps1rxnbtub.png[/img]

It was simple enough to remove.  3 screws holding it on and then I just had to run a knife through the caulk and then just wiggle it free from the sticky butyl putty tape.  Once it was off I cleaned the side up.

[IMG]http://i1357.photobucket.com/albums/q752/CamperDude/water%20inlet%205_zpslkgav4pj.png[/img]

Here is the new part that cost $18 that I picked up at my local RV store.  It came with 3 new screws, teflon tape, and butyl putty tape.

[IMG]http://i1357.photobucket.com/albums/q752/CamperDude/water%20inlet%204_zpsavbqnyxc.png[/img]

Here is the new Water Inlet screwed into the water line.
[IMG]http://i1357.photobucket.com/albums/q752/CamperDude/water%20inlet%203_zpspjan9lmp.png[/img]

And the final picture of the finished Water Inlet.

[IMG]http://i1357.photobucket.com/albums/q752/CamperDude/water%20inlet%202_zpslum4dpbl.png[/img]