Replacing And Repairing A Leaking Or Broken RV Water Pump

The water pump on an RV is the heart of the water supply system. When it no longer works or has sprung a leak, the results can certainly put a damper on adventure. Fortunately, replacing or repairing the pump is a relatively simple task. 

Preparing To Remove An RV Water Pump

Locating The Pump

The first step is to locate the water pump.

The pump is usually behind a panel in the interior of an RV. Sometimes it is found in the kitchen area, often under the refrigerator. It may also be found in one of the bathrooms behind a panel. If the water pump is leaky, the leaking water will typically lead you to the pump’s location. 

Removing Water And Power

Once you have found the water pump, take pictures from various angles of the pump, focusing on where the inlet and outlet lines connect. This will help when installing the new pump or reinstalling the old pump to ensure that it is oriented correctly. The next step is to turn off the water pump and disconnect the RV from power.

Disconnecting the RV from both shore power and the battery will help protect any additional components (such as the RV control board in the picture above) that may have gotten wet from either the leak from the pump or any additional water that may be in the water lines leading to or from the pump. It will also keep you from getting shocked while working on the pump.

Next, turn on a sink or two in the RV to allow as much water as possible to drain out of the water lines before removing them from the pump.

It is a good idea to place towels under each side of the water lines that connect to the pump before removing them in order to absorb any water that may still be in the lines. 

Removing The Pump

Disconnecting Wires

There are usually a few wires that lead to the water pump to supply power, and often to signal a pressure switch so that the pump turns off when the pressure is satisfied. It is good practice to mark each one of these wires or terminals with different colored markers, especially if the wires are all the same color.

After marking the terminals, take a picture of the marked wires while they are still on the water pump. You will want to refer to this picture when installing a new pump or reinstalling the repaired pump so you will have the right configuration. Next, remove the wires from the pump. 

Disconnecting Plumbing

With the towel(s) in place underneath the pump, loosen the inlet water line and remove it from the pump allowing the towel to catch and soak up the water that may come out from both the pump and the supply water line.

Do the same on the discharge side of the pump. Because the discharge side of the pump is supplying water to the rest of the RV there may be more water that comes out of this water line. It is a good idea to have additional towels or even a basin ready to catch that water. 

Generally, the water pump has four screws that hold it to the RV floor. Remove all of the screws and remove the pump from its location.

Installing An RV Water Pump

If you are replacing the pump, you can begin reinstalling the new pump into the location where the old pump was installed. Threading the screws that mount the pump to the RV floor so that you can see the tip of the screw at the bottom of the mounting feet can help you find the hole that the pump is going to be screwed back into.

Doing this on the front two mounting feet first will typically allow the back two mounting feet to align with the original screw holes. 

Connecting To Plumbing

Once the pump has been secured to the floor of the RV, attach the supply and discharge water lines to either side of the pump, making sure that the water flow arrow is oriented in the direction of water flow. Referencing the pictures that you took at the beginning of the pump replacement can help.

Tighten the water lines securely but only hand tight, making sure not to cross thread the fittings. A trick to ensuring that the fittings do not cross thread is to turn the fitting in a loosening motion until a click is either heard or felt. The fitting should thread on easily. 

Connecting Wires

Once the water lines are installed, put the wires back on the terminals, referencing the picture you took of the marked wires. Clean up any additional water that may still be around the pump from removing the water lines. 

Checking For Leaks

Reconnect the RV to power, either through shore power or with the battery.

Turn on the water pump and inspect for leaks. If you find a leak, turn off the pump and the power to the RV and see where it is coming from. Normally you will find that a fitting is not as tight as it should be. Tighten further by hand and restore power and water. 

Repairing An RV Water Pump

Repairing the water pump requires the same steps to uninstall the pump and reinstall it. Many parts repair kits come with instructions on how to replace specific components. However, the instructions can often be vague or for multiple pump styles, so it is important to understand which model of pump you are working with to ensure you are following the correct instructions. 

Fixing The Leak On Our Pump

I noticed that the pump in the Unique Camping + Marine company travel trailer had a crack in the plastic housing. Rather than replacing the entire pump, we ordered parts to replace only those that were damaged–the front of the pump housing, or the face plate. The kit we ordered included new screws and a new pre-lubricated gasket along with the face plate.

The process: first I removed the nine screws from the face plate and separated it from the pump motor. I then inspected the diaphragm on the pump motor for any cracks or potential damage.

Finding none, I installed the new gasket.

I installed the new screws and washers, making sure to follow the pattern on the old faceplate for the positions of the split lock washers and the standard washers.

Holding the pump motor in one hand and aligning the faceplate with the other hand. I gently pressed both parts together so that there were no gaps around the outside.

Starting at the top of the pump at the 12 o’clock position, I tightened the screw. Then I tightened the screw at the 6 o’clock, 9 o’clock, and 3 o’clock positions.

I then tightened the screws at the 10 o’clock, 4 o’clock, 8 o’clock, and 2 o’clock positions.

After tightening all of the screws, I reinstalled the pump, restored power and water and checked for leaks. Finding no leaks, I began searching for other leaks that may have developed because of freezing temperatures over the winter. 

The Takeaway

There can be many different reasons for a pump malfunction or leak. If the motor on the pump is at fault there may be no other choice but to replace the pump entirely. Sometimes it can just be the housing or one of the fittings. In those cases it is certainly far cheaper to replace just parts vs the whole pump.

Some people do not feel comfortable working on such an integral part of the RV water system. As a result they would prefer to have a professional technician take care of it.

Because a leak in the RV can lead to issues in the flooring and storage areas, some folks would rather not risk taking care of it themselves, which is completely understandable. It really comes down to one’s confidence in mechanical repairs.  Keep in mind that most warranties require that any repairs must be done by a professional. So you may or may not want to tackle this type of repair. 

But be sure to check out our video of the process for removing, repairing and reinstalling the pump in our company RV. We also have many other videos and resources available online. They are worth watching, and should help you decide whether or not you want to tackle a project like this on your own. Either way, we hope you were able to learn something from this write-up.

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