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If you notice that your camper has a leak, you need to address the issue as quickly as possible, but what do you do when the leak is underneath the RV?

Whenever you see a leak in your camper, regardless of its size or where it’s located, you must resolve it before it gets worse. A failure to do so can result in serious issues with your camper and it could potentially cause irreversible damage. However, with so many components connected to water and plumbing on your camper, you need to find out exactly where the leak is coming from.

When your camper is leaking water underneath, turn off all water coming into the vehicle and close all faucets. Next, drain all water from the vehicle and perform a pressure test using an air compressor. The escaping air will create a hissing sound, which will pinpoint the leak so you can fix it.

When you first buy a camper, you may be surprised by just how much maintenance is involved in owning one of these vehicles. Unlike a standard car, RVs are equipped with a bulk load of features and components that all need to be looked after. With that said, owning an RV is a lot like owning a house, as you have to deal with the same kind of upkeep, which includes dealing with water leaks. When you spot a leak in your RV, you better believe it’s going to get worse before it gets better and it may end up damaging other components of your vehicle. Leaks can be particularly obscure when they are underneath your camper with no clear indication of where it’s coming from. To help you understand this further, we are going to take a closer look at what you should do when your camper is leaking water underneath.

After extensively researching RV maintenance and troubleshooting forums, I have been able to gather enough information to determine what causes a camper to leak water underneath. My research has indicated that you should always check your owner's manual when troubleshooting a leak in your RV, as the components connected to the issue can be in different locations depending on the make and model of your camper.



What to Do When Your Camper is Leaking Water Underneath

While it may seem instinctive to start investigating the leak while the water is still flowing, you want to prioritize avoiding any unnecessary damage from happening to your camper.

Every second that leak continues underneath your RV, the chances of your vehicle getting water damaged increase. That is why the first thing that you want to do is turn off all water coming into your RV.

  1. Turn off the water hookup
  2. Close all faucets in your camper

If you are able to get the water off in time, you should be able to prevent anything serious damage that is beyond repair.

Reasons Your Camper is Leaking Water Underneath

Before you can begin fixing the leak underneath your camper, you need to first figure out where the source is. Your camper has several different components and functions connected to the vehicle’s water supply, and any one of them could potentially be causing the leak.

As soon as you have turned off the water to your vehicle and closed all faucets, check outside the camper to see if you can spot a specific area of the RV where the water is coming from. You may be able to see the leak right at its source or perhaps at least identify what it’s connected to.

Once you are able to spot the source, you will have a much easier time fixing the problem. If you can see the area that it is coming from but you are unsure which component it’s connected to, grab your vehicle manual, as this will have a blueprint of your entire camper. With that said, these are the most common reasons that a camper will leak water underneath.

Broken Hoses

Hoses are often one of the main culprits behind water leaks. A hose could have been punctured, ruptured, or it may have just come loose.

Broken Water Pump Valve Seal

Your camper has a water pump that could be causing the leak underneath the vehicle. The most common reason for this would be if the water pump seal got worn out over the years.

Cracked Water Tank

Although water tanks are built to be quite durable, it is not uncommon for one to rupture or crack.

The water tank may have been met with some kind of impact which resulted in it cracking and leaking. If the leak is large, it should be pretty obvious, as there will be a lot of water coming out.

Broken Water Heater Seals

If your water heater is leaking from the tank itself, it should be pretty easy to spot. However, what is much more likely is that one of the water heater’s seals has ruptured and is causing the leak.

Overfilled Tanks

It is easy to confuse a legitimate water leak caused by damage to your plumbing with a simple overfilled tank. If you just recently filled your tank with water, there is a good chance that you may have overfilled it, which is causing it to leak water.

Alternatively, it may have been a while since you dumped your black or grey water tanks, which can also potentially leak when overfilled.

Damaged Black & Gray Water Tanks

Your camper should have two tanks for storing wastewater - your black and gray water tanks which are located underneath the vehicle.

These can get damaged if met with strong impact and figuring out if they are causing the leak can often be obvious due to a foul smell coming from the spillage.

How to Locate the Water Leak Underneath Your Camper

The issue with finding a water leak underneath a camper is that it can be a bit obscure and challenging to pinpoint. If you are lucky, you will be able to see the source of the leak by checking underneath the vehicle or looking for signs inside your RV.

However, this can be easier said than done, especially if the leak is small and not visible to the naked eye. In this situation, you need to perform a pressure test on your camper so that you can diagnose the leak further.

If you want to perform this test and handle the repairs yourself, you are going to need an air compressor, as well as a pressure gauge. You can pressure test your camper and locate the leak by following these steps:

  1. Drain all water from the vehicle
  2. Attach the air compressor and gauge to the water inlet valve
  3. Inject 100psi of air into the system
  4. Wait for 5-10 min (a drop in pressure indicates a leak)
  5. Examine your RV and listen for a hissing sound

Although the leak appears to be coming from underneath your camper, do not rule out the possibility of it being somewhere inside, as it could simply be draining below the vehicle. Be thorough and check your vehicle carefully. Once you identify where the hissing sound is coming from, you will have found the source of the leak and you can begin taking steps to fix it.

If you were not able to find the leak, you can try adding some water back into the system and repeat the pressure test to see if this can give you a visual of the leak. In case the leak is particularly hard to find, remove the underbelly cover from your camper so that you can get a better idea of the source.

How to Fix a Camper When it is Leaking Water Underneath

Given that a water leak in your camper can be connected to so many different parts and components, there is no one-fix-all solution to this issue.

Recreational vehicle mechanics and plumbing systems can be complicated and intricate, which is why if you are not an experienced RV mechanic, you should carefully consider whether you are up to the job of fixing the leak yourself.

After you have found the source of the leak underneath your camper, you may be able to fix it by buying replacement parts or using patching materials.

Patching Cracks & Punctures

There’s a good chance that the leak is connected to a small crack in either a pipe, hose, or one of your tanks. Not every leak implies that you need to replace the entire component connected to it.

You may be able to solve the problem simply by patching it up, which is a lot cheaper and easier. To do so, consider using the following supplies:

  • Calk
  • Pipe leak tape
  • Pipe putty

If the leak is large and the component cannot be properly patched, then you will need to replace the entire part.

Pipe & Hose Replacements

Damaged pipes and hoses are common reasons for a camper to leak water. If you are able to find the exact pipe or hose underneath your camper, you can fix the leak by replacing it with a new one.

This is going to be necessary if the crack or puncture is beyond a patch job, which you may want to consider doing anyways in case the sealant breaks.

Gasket and Seal Replacements

After years of use, your vehicle’s gaskets and seals will start to get worn out and eventually rupture. If one of the gaskets or seals in your camper is responsible for the leak, these cannot be repaired and will need to be replaced.

To do so, you will need to find out exactly which component is causing the leak so that you can buy and install a replacement gasket or seal.

Tank Replacements

Whether it is your water tank or one of your black or grey water tanks, if it has been seriously damaged and ruptured, patching it up may not be worth the effort. In this case, you will need to replace the entire tank, which can be costly and challenging.

Depending on the make and model of your camper, you will need a specific tank that is suitable for your vehicle. Make sure that you follow the installation procedure carefully as instructed by the manufacturer.