How To Install a Water Tank Under a Van

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One of the biggest issues with van life is carrying all your water. It’s heavy, it takes up precious space inside your van, and if you run out…well, it can be a real pain to get more. That’s where the water tank comes in, but how do you install a water tank under a van?

Here’s how to install a water tank under a van in 6 steps:

  1. Choose the location of the water tank.
  2. Mount the mounting block to your van.
  3. Drill holes near your mounting block for piping and electrical wires.
  4. Attach the RB Components Sprinter Water Tank with plumbing fittings.
  5. Cover the tank with Rust-Oleum flat black spray paint for protection.
  6. Make sure everything is working correctly.

In this article, I will walk you through how to install a water tank under a van in these six easy steps. The tools needed for the project include RB Components Sprinter Van Water Tank and Mounting Kit, eight Hanson Rivet Multi-Grip Rivet-NUT, Astro Pneumatic Tool Plusnut, Rust-Oleum Flat Black Spray Paint, DEWALT Drill and Impact Driver, and a Liftmaster Heavy Duty Car Jack (all available on

1. Choose the Location of the Water Tank

The first step to installing your water tank is to choose where you want to place it. This can be anywhere that doesn’t impede access or drivability of your vehicle or put people at risk.

It needs to be in an open area away from low-hanging objects or obstructions that could interfere with incoming airflow.

Here are some guidelines to help you pick the most suitable location for the water tank:

  • The tank should not extend beyond the width of your van
  • Do not place the tank near a heat source or near any other items that could potentially ignite.
  • Do not place the tank in a hazardous area where chemical fumes accumulate, such as diesel fuel storage areas.
  • It would help if you placed the tank away from any moving parts of your vehicle, such as suspension springs and door hinges.

Tip: The vented cap should not be blocked. Once you have found the right location, make sure to clean this area thoroughly and around it as well with a degreasing agent to remove any gunk or dirt that may interfere with your installation.

2. Mount the Mounting Block to Your Van

The mounting block for your water tank can be attached either with bolts or rivets, depending on how much weight you expect the tank to hold.

Bolt holes, also known as umf’s (universal machine fasteners), are located near each corner of the mount with matching bolt holes in the bottom of your tank so you can screw it down securely.

Using bolts, drill pilot holes through one side of your van’s interior sidewall and slide washers before adding nuts below.

Attach a washer and nut to the outside, then tighten with a socket wrench. You can install rivets in holes on either side of the mount near each corner to attach the tank securely.

Drill pilot holes through both sides of your van’s interior before using an installation kit to add rivet nuts inside and outside your vehicle.

Here are some guidelines for attaching the mounting block to your van:

  • The block should be mounted with the top facing forward and the bottom toward the floor.
  • Use washers or shims under each bolt if necessary.
  • If screwing plastic rivets, make sure to use a rivet installation kit to ensure your tank remains leak-proof.
Note: Suppose you buy a different water tank that does not come with a mounting kit. In that case, you may have to buy the mounting block separately. In such a case, I recommend choosing the stainless steel mounting hardware since this is a long-term investment and it will last longer.

Additionally, here are some of the crucial factors to consider when picking mounting hardware for your tank:

  • Make sure the hardware is compatible with your vehicle. For example, the bolts or rivets fit through your van’s walls, and the screws should fit through your tank’s holes.
  • The thickness of the metal should be strong enough to support your tank without being too heavy or taking up too much space in your van.
  • Your water tank might have a lip with raised edges around the top, so find hardware strong enough to hold onto this particular feature securely.
  • It should be weather-resistant, rustproof, and mold-resistant since it will be exposed to different weather conditions.

3. Drill Holes Near Mounting Block for Piping & Electrical Wires

After you have mounted the water tank’s mount block, it’s time to drill some holes through your van’s interior walls for both the intake and exit piping as well as electrical wires coming from the wiring harness near your battery.

Make sure you measure the placement of your holes carefully to prevent drilling into something you don’t want to, such as your van’s brake lines, fuel lines, or wiring.

Make sure that they are far enough away from low hanging objects or obstructions that could interfere with incoming airflow but not so close together that they are crowded.

Use a marker on your van to mark where you want them drilled before setting up your water tank on top of these locations so it can help keep it steady while you work.

Here are additional guidelines to consider when drilling the holes for piping and electrical wires:

  • Electrical wires should be drilled near your van’s power source
  • For metal van exteriors, use rubber grommets to protect cable insulation from sharp edges around openings that could expose wiring or cause injury if it is handled improperly.
  • The holes for piping should be slanted to allow water to drain properly
  • You will need to drill twice as many holes for piping if you are installing additional faucets.
  • The holes should be large enough to allow the pipes to fit through snugly but not so large that they are oversized.

4. Attach RB Components Sprinter Water Tank w/ Plumbing Fittings

Your water tank comes with the plumbing fittings, hoses, and faucets you need to set up your system.

Attach one end of a braided steel flexible water hose to the top of your tank’s spigot(s), then attach the other end to each corresponding plumbing fitting on your van. You can then use adjustable crescent wrenches or pliers to tighten them until it is secure.

Next, connect each electrical wire from these openings to its corresponding port on your power source using an insulated wiring connector.

Once they are all connected, attach your water tank to the mounting block with washers and nuts from underneath. Do not tighten any bolts until everything is secure, especially if you are using a flexible hose.

Make sure they are secure by testing your tank after you have mounted it to the block. Also, don’t forget to add foam insulation or weather-stripping under your tank to prevent condensation under the tank.

Here’s how to add weather stripping to your newly installed water tank in 6 easy steps:

  1. Clean the underside of your tank with a damp cloth
  2. Cut and attach weather stripping around the entire perimeter using strong adhesive tape or glue that won’t damage your tank’s exterior
  3. Ensure that it fits snugly and is completely sealed against the surface of your water tank by testing its seal with a hose after attaching it
  4. If you used adhesive, allow 24 hours to dry before re-installing your metal mount block onto your van’s mounting plate
  5. Add foam insulation under each side of your tank if necessary
  6. Reattach the bolts for each corner so that they are securely attached but not too tight where they could cause damage to valuable components such as wiring, and then tighten them all evenly and then fully.

Here are additional guidelines to follow in this step:

  • Do not make any of your connections until everything else is in place
  • Make certain that the fittings you attach are compatible with your tank and van.
  • No joints should be exposed to a heat source, such as the exhaust piping or engine, or high-pressure areas like near brakes, fuel tanks, or accelerators.
  • If you are using flexible hoses, make sure they will not interfere with opening doors before tightening them down
  • Gently tug on each hose to make sure they can take stress before moving on.

5. Cover the Tank With Rust-Oleum Flat Black Spray Paint 

The flat black spray paint will help protect your water tank against rusting or cosmetic damage so it can remain sturdy and durable for years to come.

Once you have attached the tank to its mounting block, spray paint over all surfaces, including the bottom, until it has an even coat on all areas that were exposed before you began this project. Let it dry overnight before applying another coat in the morning if necessary or desired.

Here’s a video that will come in handy when following these steps:

Besides spraying the tank with Rust-Oleum, here are other ways to ensure you make the most of your newly installed water tank:

  • You can install a temperature and pressure release valve to make sure your piping does not freeze or expand.
  • Secure it with tie-downs near the front of the van’s frame for extra protection against accidents. You can also use cam locks or steel strapping if you prefer.
  • Make sure the power source works by turning on each faucet one at a time until they are all running properly.
  • Use only purified water in your tank; there may be dangerous chemicals present in tap water.
  • Clean, disinfect, and refill your tank every six months (once a year is the minimum recommended frequency) for optimal performance.

Here are six easy steps to clean and disinfect your tank:

  1. Remove the tank lid and clean it with warm soapy water.
  2. Use an antibacterial cleaner to remove stains, mold, or mildew from the tank’s interior
  3. Rinse it thoroughly with clean water.
  4. Sanitize your tank with a solution of chlorine bleach and water (⅓ cup bleach for every gallon/ 3.8 liters of water). You can also use this method if you have drained your tank before storing it for extended periods of time. Be sure to rinse it thoroughly once you are finished.
  5. Move your tank into its final position and replace the lids.
  6. Check for any leaks or damage before storing it away until your next trip. If you find any issues, contact RB Components right away so you can fix the problem and use your water tank as soon as possible.

6. Make Sure Everything Is Working Correctly

Now that you have installed your water tank, connected the system, and painted it for protection, all you need to do is make certain everything is working correctly before hitting the road.

You will need at least one gallon (4.54 L) of water to test your system, but these steps will help verify everything is working properly after it’s installed:

  1. Turn on each faucet individually and wait for approximately one minute before moving on to the next (two minutes if you have multiple spigots).
  2. When all spigots are running, wait another minute to make sure they are all connected to the same water supply.
  3. Check the temperature, pressure, and flow rate of your faucet.  

Use this information in case you need to contact RB Components if any parts or components break down later on so you can fix them right away instead of waiting for an emergency.

Final Thoughts

When you are ready to use your water tank, remember these important safety tips: 

  • Make sure you have the proper sized hoses. 
  • Use only potable or purified water so that you don’t poison yourself while cleaning or cooking food. 
  • Remove any debris from the tank before filling if there is anything in it already, such as dirt, twigs, and leaves. It could cause damage if it’s allowed to mingle with the rest of your system while traveling down your plumbing. 
  • Check all faucets and components for any damage or leaks regularly.

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