How to Repair an RV Gray Water Valve

How to Repair an RV Gray Water Valve
The gray water tank on an RV holds water from the sink and shower drain. Over time the seals in the gray water valve will break down and leak. The valve itself will wear from normal use and begin to leak as well. Repairing a gray water valve is easy and should be done as soon as a leak is discovered. Not repairing the valve will cause the leak to get worse and create more and bigger messes that need to be cleaned.


Difficulty: Easy

Disassembling the Valve

Things You’ll Need:
  • Bucket
  • Rag
  • 2 wrenches to fit the bolts and nuts of the gray water valve
Step 1
Completely drain the gray water tank using an appropriate dump station.
Step 2
Place the bucket under the gray water valve to catch any water that remains in the line.
Step 3
Locate and remove the four bolts that are used to attach the center part of the valve to the valve flanges. Put one wrench on the bolt head and the other on the nut to remove the bolts. Set the nuts and bolts aside.
Step 4
Slide the center part of the valve out from between the flanges. You may have to tap the valve to break it free.
Step 5
Remove the old seals. In most cases these will be O-rings, although the manufacturer may have used rubber gaskets.

Reassembling the Valve

Step 1
Use the rag to dry and clean the flanges and seal surfaces.
Step 2
Install new O-rings into the grooves in the flanges for them. If the valve uses gaskets, line these up with the holes and hold in place with the bolts.
Step 3
Put the new center part of the valve in position between the flanges. Be careful not to move the seals from their positions.
Step 4
Insert the bolts all the way through both flanges and the center part of the valve.
Step 5
Thread the nuts onto the bolts and finger-tighten.
Step 6
Progressively tighten the bolts. Apply even pressure to the valve by working from one bolt to the opposite bolt until the bolts are "good and tight."

Tips & Warnings

To keep your hands clean wear latex dishwashing gloves.

Article Written By Mark Quest

Mark Quest began his writing career in 2009, contributing to various online publications. He attended Asheville Buncombe Technical Community College, focusing on the sciences.

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