Here is a compendium of tips from folks that responded to a leak around the City Water Fill:
- I had the same problem with fresh water and they changed the city
water valve that stops the water from coming out the city water valve when
using the pump..   Bill Azar
- We had this same problem on an old motor home as we drove down the road water
was squirting out the side, we had to replace the check valve but you might
try to stick something like a small screw driver into the opening I think
there is a ball and spring to stop the water from back flushing.  There might
be some small debree caugh in it.  Let me know if this helps...Joe Rossi
- The city water inlet will leak when it gets corroded with hard water deposits or dirt.
One quick fix is to turn the punp on and then go outside and push
the little plastic center portion of the inlet.   Water will spray in your
face, but do this several times then make sure the center of the inlet is
facing straight out, not bent over to one side.   If this doesn't stop it you
need a new inlet, which you can get from any dealer and there very easy to
replace, Turn pump 0ff and remove the two screws then reach under the inlet
housing and unscrew the fitting.  Reverse the procedure to put the new one on...Bob Nelson
- You may be able to back flush the city water valve instead of replacing it.
It may have a piece of dirt holding the rubber flap away from it's seat.
Just pry the inlet screen out of the hose connector on the D.   Then with
water in your fresh water tank, and the water pump turned on, push the rubber
flap in and away from it's seat with a smooth instrument that won't poke a
hole in the rubber.   Stand clear of the city water fitting when you do this,
or you will get plenty wet.   If dirt is the culprit, it will be back flushed
out of the fitting using this method.   You can do this several times until
you notice that the valve is sealing properly when the dirt is gone.   When it
seals properly, replace the screen and you're done...Joe Brown
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