What You Need to Know Before Starting
Replacing a camper toilet is a job you can do yourself in two to four hours with basic hand tools and no plumbing experience. The toilet bolts to the floor from underneath, connects to a waste tank below, and usually sits on a rubber seal. You will need to shut off water, drain the tank, unbolt the old toilet, and install the new one with fresh sealant. Most camper toilets cost between $150 and $400, and doing the work yourself saves the $200 to $500 labor charge at an RV service center.
The hardest part is not the removal—it is keeping the waste tank from spilling when you disconnect the outlet. You will also need to work in a tight space, often on your back or crouching, so plan for discomfort and give yourself time. The job is straightforward enough that mistakes are rare, but rushing the sealant step is the most common reason a new toilet leaks.
Key Takeaways
- Turn off the water supply at the tank or the valve behind the toilet, then flush to empty the bowl and lines.
- Unbolt the toilet from the floor, disconnect the water inlet and waste outlet, and remove the old rubber seal ring.
- Install a new rubber seal on the flange, set the new toilet in place, and bolt it down hand-tight before tightening fully.
- Reconnect water and waste lines, turn the water back on, and let the toilet sit for 24 hours before use so the sealant sets.
- Test for leaks at the base and around all connections before you put the camper back into service.
Gather Your Tools and Materials
You will need an adjustable wrench or socket set (usually 7/16-inch or 1/2-inch bolts), a screwdriver, a putty knife or old credit card, a bucket, towels, and a sponge. Have a flashlight or headlamp ready because you will be working in dim spaces. Wear gloves—the waste tank connection is not pleasant.
For materials, buy a replacement toilet that matches your camper's size (most are 20 to 24 inches wide), a tube of marine-grade silicone sealant (not regular caulk), a new rubber seal ring that comes with most new toilets, and a bucket of water or a hose to rinse. If your old toilet has a metal flange bolted to the floor, check whether the new toilet uses the same bolt pattern—most do, but confirm before you buy.
Turn Off Water and Drain the System
Locate the water shutoff valve. On most campers, it is behind the toilet or under the sink, or it may be a main valve near the fresh water tank. Turn it clockwise until it stops. If you cannot find a valve, turn off the water pump itself—usually a switch on the control panel or breaker box.
Flush the toilet to empty the bowl and lines. If water does not drain, the tank may be full or the valve may not have closed completely. Flush again and wait a few minutes. Open the cabinet or access panel under the toilet so you can see the waste outlet and water inlet lines. Place a bucket underneath the waste outlet—there will be residual liquid even after flushing.
Remove the Old Toilet
Disconnect the water inlet line first. It is usually a flexible hose or a compression fitting. Use your wrench to loosen the nut where it connects to the toilet base, then unscrew it by hand. Water may drip—that is normal. Catch it with your bucket or towel.
Next, disconnect the waste outlet. This is the large hose or pipe that runs from the bottom of the toilet down to the tank. Loosen the hose clamp with your screwdriver (turn counterclockwise) and slide the hose off the outlet. Brace the hose so it does not spill into the bucket—you may need to pinch it closed or have a second person hold it. If the connection is glued, you may need to cut the hose and replace it with a new one.
Now unbolt the toilet from the floor. There are usually two or four bolts underneath, accessed from the side or front. Use your wrench to loosen each bolt, then unscrew them by hand. Lift the toilet straight up and set it aside. Do not rock it side to side—you want to break the old seal cleanly.
Use your putty knife to scrape away the old rubber seal ring and any dried sealant from the flange (the metal ring bolted to the floor). Wipe the flange clean with a damp cloth and let it dry completely.
Install the New Toilet
Place the new rubber seal ring onto the flange, centered on the bolt holes. If the ring is not pre-installed on your new toilet, press it firmly into place by hand. Run a bead of marine-grade silicone sealant around the underside of the toilet base where it will contact the seal ring—this creates a watertight bond.
Lower the new toilet straight down onto the flange, aligning the bolt holes. Do not twist or rock it. Insert the bolts by hand and tighten them in a cross pattern (like tightening a car wheel)—tighten one bolt a quarter turn, then the opposite bolt a quarter turn, and repeat until all bolts are snug. Do not over-tighten. The bolts should be firm enough that the toilet does not move, but loose enough that you can still turn them with your wrench. Over-tightening cracks the porcelain.
Let the sealant cure for at least 24 hours before you use the toilet. This is the most important step for preventing leaks.
Reconnect Water and Waste Lines
Reconnect the waste outlet first. Slide the hose back onto the outlet and tighten the hose clamp with your screwdriver. Make sure the clamp is snug but not so tight that it crushes the hose. If you had to cut the old hose, install a new one of the same diameter (usually 1.5 or 2 inches).
Reconnect the water inlet line. Thread the nut by hand first to avoid cross-threading, then use your wrench to tighten it. It should be snug but not so tight that you strip the fitting. Turn the water supply back on at the valve or pump. Check for leaks at the water connection—if water drips, turn off the supply and tighten the nut another quarter turn.
Flush the toilet slowly and watch for leaks at the base and around both connections. If you see water pooling under the toilet, turn off the water when ready and let the sealant cure longer. Leaks at the base usually mean the seal ring did not seat properly, which requires removing the toilet and reseating it.
Test and Troubleshoot
After 24 hours, flush the toilet several times and observe for leaks. Check the base, the water connection, and the waste outlet. A small amount of condensation on the outside of the waste hose is normal, but water pooling or dripping is not.
If the toilet rocks when you sit on it, the bolts may be loose. Tighten them a quarter turn at a time in a cross pattern until the toilet is stable. If water leaks from the base after 24 hours, the sealant did not set properly or the seal ring did not seat. You will need to remove the toilet, clean the flange and base again, and reinstall with fresh sealant.
If the waste outlet leaks where it connects to the hose, tighten the hose clamp. If it still leaks, the hose may be cracked or the outlet may be damaged. Replace the hose or contact the toilet manufacturer for a replacement outlet.
Frequently Asked Questions
Do I need to replace the rubber seal ring every time I remove the toilet?
Yes. The rubber ring compresses and deforms when the toilet sits on it, and reusing it often causes leaks. A new ring costs $10 to $20 and is worth the peace of mind. Most new toilets come with one included.
What if my camper toilet is bolted directly to the floor with no flange?
Some older campers have toilets bolted straight to the subfloor. Remove the bolts, scrape away the old sealant, and install the new toilet the same way. Use marine-grade silicone under the base and let it cure 24 hours before use.
Can I use regular caulk instead of marine-grade silicone?
No. Regular caulk breaks down when exposed to water and waste chemicals. Marine-grade silicone is formulated to resist moisture, UV light, and tank chemicals. It costs a few dollars more and lasts much longer.
How do I know if my new toilet will fit in my camper?
Measure the width and depth of your old toilet, and check the bolt hole spacing on the flange. Most camper toilets are 20 to 24 inches wide and use standard bolt patterns. Bring your measurements to the RV supply store or check the product specs online before you buy.
What should I do with the old toilet?
Most RV supply stores or waste management facilities will take old toilets for recycling or disposal. Some charge a small fee. Do not throw it in the trash—it takes up space in landfills and the porcelain can break and injure workers.