Older model LDs came from the factory with the Shurflo city water inlet, characterized by a squarish plastic flange mounted with four screws. This design conveniently has built in both a check valve for the internal plumbing and a pressure regulator for external water supply. Unfortunately, its design and materials make it leak-prone as it ages, and these leaks may go undetected for years and cause significant damage.
The construction is plastic, and combined with marginal engineering, warpage eventually allows the internal seals to fail to retain pressure, even if never used to actually connect to city water. Additionally, as the plastic ages, it can eventually crack and cause a dramatic loss of pressure, and this is when prior leakage damage may be discovered. It is recommended that this unit be replaced as a regular maintenance item before problems become serious, as there is no improved direct replacement.
The Valterra city water inlet can be substituted, though it mounts with three screws and the original mounting holes must be plugged. A small area of unpainted aluminum will also show around the perimeter. This unit is all metal and will not fail, but an external pressure regulator must be used when city water is connected.
If your problem is with a newer inlet with a no-longer functioning check valve, it is possible to replace the check valve without having to replace the entire water inlet.
How to replace the inlet:
Expect to spend about 1.5 to 2 hours to remove and replace the city water connection.
Great care is required and it is recommended that you use a piece of heavy cardboard under the tools to keep the tools from scratching the side of the RV.
First, use an Exacto knife to painstakingly cut away the caulk at the edges of the round housing. Then working with a sharpened putty knife, tap the top of the putty knife with a hammer to pound it under and through the caulk around the underside of the housing.
Then gently pry up the round housing with two putty knives on opposite sides. When the underside of the housing is pretty much clear of putty, attach a right angle hose fitting to help pull the housing away from the aluminum sidewall of the RV. Then cut the thick band of putty underneath.
Finally, pull the housing away from the RV wall and expose the inside fitting, which can be separated from the outside fitting using two wrenches.
Reattach the new housing (using teflon tape and the old rubber insert-gasket) and check for leaks. Then apply new putty and screw the new housing back into the RV wall. Done.
The replacement unit sold by Camping World for around $7 fits perfectly. It looks almost identical except it is white.
Contributors: Bob, Steve
Revised 20 Nov 11