Bottled Water for RV Toilet Use

We are newbies at this, and it's our first winter. If we winterize our 5th wheel, and then want to go camping in the winter, is it safe to use the black tank with bottled water only? Since the black tank hoses appear to be quite large it's hard to believe they would freeze. Or are there smaller hoses somewhere in the black tank system that we can't see that could freeze? We would be using bottled water only for any fresh water needs, so we wouldn't disturb the anti-freeze in the rest of the system. Is our thinking right on this? Barb H. 

Barb, it is perfectly doable to use the black tank with bottled water if you choose that route. It’s also possible to use the complete fresh water system in the coach during the winter with some proper preparation. See my winter RVing article here. But typically it’s a full 3-inch drain from the toilet into the solid waste holding tank so just pouring bottled water into the toilet before and after each flush, you should be fine. I’d add a little RV anti-freeze to the bottom of the holding tank just to keep it from freezing if you’ll be in extended below-freezing weather. And remember, you’re in an RV so you can always head south!

##RVT774; ##RVT882

RV Toilet "Scored" And Not In A Winning Way!

You have helped me several times in the past and now I have a minor problem. The toilet brush we have been using has really "scored" and scratched our RV toilet badly. I have managed to get rid of the gouges with rubbing compound and then car wax. My question is: What can we use to clean the toilet without leaving the scratches? (We think the brush we were using is designed for ceramic toilets). Many thanks! John E., (via RV Doc Newsletter)

John, I’m not a big fan of plastic RV toilets for the very reason you mention. They are simply not compatible with most abrasive cleansers and bathroom brushes. I think you’ve done the best thing you can to rectify the issue though. If the car wax contained carnuba, that will help. Future cleansings should be performed with a strictly, non-abrasive cleaner and use a very soft brush. Personally I don’t have a favorite, so any non-abrasive cleaner is a potential. It may take some experimenting to find the one best suited for you. 

##RVT896

RV Toilet Leaks

I have an older Tioga motorhome. The hoses connecting to the toilet are leaking. I cannot reach the connections because of the tight space, but I can see the leak with a mirror. My question is, can I access the connections another way without removing the toilet completely? It looks like the toilet might be able to be separated top and bottom. There is a seam there. If I do need to remove the toilet do you have any advice? Todd H. (San Diego, CA)

Todd, there are a few reasons why water may be leaking at or near an RV toilet. By checking where the water is coming from and exactly when the water appears, you can pinpoint which cause is the culprit. If water drips to the floor from the upper portion of the toilet only during the flushing cycle, the problem is most likely the vacuum breaker. Typically a float seal in the vacuum breaker assembly is not sealing properly. On some units, the float can be disassembled and cleaned. Other models will require a repair kit. Still others may require a completely new vacuum breaker. 

Sometimes water will appear to be leaking only if the bowl is filled to capacity. There is a slight possibility the bowl is cracked at a point above the normal water level. This is not a very common situation, but it does happen occasionally and is usually caused by improper winterizing techniques. This is only possible with toilets made with plastic bowls. 

Water may also be noticed around the base of the toilet with no apparent or visible dripping from above. Chances are the seal between the flange and the base assembly is faulty which requires toilet removal and reinstallation. If water leaks onto the floor after the flush cycle has completed, or without flushing the toilet at all, the culprit is the water inlet valve or the connection to the valve. 

This is what you and I both suspect with your toilet. Let’s assume it’s simply the connection at the water inlet valve that is leaking. Though the space may be tight, it’s often possible to tighten the fitting at the inlet to stop the leak. I’ve used a basin wrench in the past to reach behind the toilet and tighten the fitting without having to remove the toilet at all. 



Though you didn’t mention the brand, I believe Fleetwood used the Thetford Aqua Magic toilet in their Class Cs of old. If it’s absolutely necessary to remove the toilet from the floor flange in order to gain proper access to the inlet fitting, you’ll have to remove the nuts on the two closet bolts, which can be difficult a difficult task without the proper tools. 

On the Aqua Magic the bolts are located at the 5 o’clock and 11 o’clock positions when standing in front of the toilet. There should be an access hole under the seat to reach the back bolt at the 11 o’clock position. A long socket extension with a universal joint will be needed to remove that one; or a ratchet wrench can be used by reaching around the rear of the toilet. It’s a blind feel, but doable. 

The front bolt is accessed by turning off the water supply and depressing the pedal. It will be apparent. But I’m guessing if you can gain access to the closet bolts, you can gain access the inlet fitting and the connection that apparently is leaking. I’d try the basin wrench first and only remove the toilet if necessary. Don’t forget, you’ll need a new closet flange seal if you opt to remove the toilet. Though the toilet is constructed in two sections, they do not come apart at that seam you see between the top and bottom halves.

##RVT79; ##RVT886

Whistling Motorhome and Stopped Up Waste Drains - A Two-fer!

Thanks for a great seminar! Time ran out and I didn't get to ask you two questions. Both are among the more difficult that I've ever had to deal with and I spent eight weeks at and graduated from the Camping World University, so I'm prepared to try most anything. We have a loud whistling noise when traveling over 55 mph; particularly, with a head wind. Of course, the obvious solution (to paraphrase the Henny Youngman joke), "don't drive over 55 mph!" A technician moved the mirrors out saying that it would fix the problem; wrong. Upon returning home I filled in all of the possible openings in the firewall with foam. Do you have any other suggestions? 

Also, equally challenging; I have an occasional blockage of the black water tank at the exit of the drain pipe into the tank. The solution to clearing the blockage is to stick a nozzled hose down there; a messy unpleasant task. All previous coaches have had the toilet positioned directly over the tank. Our floor plan required a double 45-degree angle into the tank. Consequently, solids enter the tank at a slower speed, and the tank depth is less at the entry point than at the rest of the tank. I believe the manufacturer recognized this design shortcoming in our 2008 floor plan by installing a macerating toilet in the comparable 2009 model. I've discontinued using the Sani-Con all together because by emptying fluids first, it merely exacerbates the problem. I had an extension added to the back flush on the tank so that it is now at the position on the tank where the solids exit as opposed to the far left of the tank. Upon returning home, I'll remove the flush and drill a hole in the end. The "nozzles" spray in multiple directions and it should help if I can get a more concentrated spray directly on the solids that accumulate at the entrance to the tank. Any additional suggestions that you may have will be greatly appreciated. Joe G. (no city/state)

Joe, the whistling problem can be a real nuisance and an even more difficult disturbance to troubleshoot. The dynamics of noises produced by moving air is an interesting study. Almost any thing or combination of things can contribute to the noise. The obvious (seemingly) culprits include air horns, TV and radio antennas, curved moldings on sidewalls, design characteristics of the front cap, window placement, etc. This is a tough one to diagnose, especially via long distance! A detailed inspection of everything on the roof and at the front of the coach is in order. Look for loose moldings, gaps in the sidewall, etc. I’ve even seen wind deflectors installed in front of air horns and antennas, but I have no proof that it truly helped. There is a product call Air-Tabs that I have not personally tested or evaluated, but it may be worth a call to the company to see if they have any recommendations regarding air movement and noise at the front of the motorhome. That’s a tough one! You could always just crank up the bluegrass music to 10 and you won't even hear the whistling noise!

As to your second question, it is unfortunate that the toilet drains through two, 45-degree elbows before entering the tank. It is code compliant, by the way, but when coupled with that offset shelf built into the design of the holding tank, it simple worsens the situation. To gain more velocity, always evacuate when the holding tank is nearly full, even if you have to add fresh water to top it off. Refilling the holding tank with fresh water and dumping again will indeed help. In fact, it is recommended to refill and dump all holding tanks in this manner when practical. (Here are my recommended dumping procedures). 

And be sure to use an enzyme-based, live bacteria-type holding tank additive to help reduce the mass of the solid waste during the time it's in the holding tank. Using copious amounts of water during each flush of the toilet may help, but it appears you are at the mercy of the floorplan. Unless you opt to replace the toilet with a macerator toilet. 

Surprise Blockage in RV Holding Tank Drain!

How do I retrieve a toilet cleaning brush, approximately 14-inches long, from the toilet-to-holding tank sewer pipe? The brush fell down the toilet and appears to have wedged inside the pipe causing clogging which fills up the pipe. Very little waste is making it to the holding tank. The pipe length from the bottom of the toilet to the entry to the holding tank is approximately two feet and has a 45-degree angle. Help! Robert H. (Santee, CA)

Robert, it's literally impossible for that cleaning brush to ever get past that first 45-degree elbow in the toilet drain. In this instance, it's actually a good thing your toilet drain has that bend in it. If it was a straight drop from the toilet into the holding tank, it would be more difficult retrieving it from the holding tank itself. 

You'll simply have to cut through the 3-inch ABS drain pipe a few inches above or below the uppermost 45-degree elbow fitting. You may have to sacrifice the brush itself in doing so, but chances are you wouldn't be using that brush again anyway! Depending on how easy it is to flex either the upper or lower section of the drain pipe after the first cut, it may also be necessary to make an additional cut in the ABS piping on the opposite side of the elbow. Making two cuts will enable you to remove that section with the brush completely and then, easily remove and discard it.

Then simply cement two, 3-inch ABS couplers to reconnect the toilet drain piping. It may be difficult to install the 2nd coupling if there's not much give to the drain pipes. If that is the case, it may be easier to install a Calder-style coupler (see photo), instead of a glued-in fitting. A worst-case situation may mandate removing toilet and floor flange in order to reassemble all the pieces correctly.

It's amazing what gets dropped down the toilet and into the holding tank; none of which is a good thing. As you found out, it definitely causes blockage issues. I even had one reader wonder how to remove a set of dentures from the solid waste holding tank! Yikes!  

##RVT795

Damaged Hinge on RV Toilet

The toilet seat hinge on one side is broken. Can it be replaced and how? A local shop said I'd have to replace the whole toilet. I sure hope not! Ed B. (Ft. Myers, FL)

Ed, in most cases, the toilet will not have to be completely replaced. The hinge can be replaced on many RV toilets, though it may entail replacing more than just the hinge. For example, on one model in the Aqua Magic line, the hinge is actually an integral component of the vacuum breaker assembly. So it all depends on the brand and model of your toilet. If you send me that information, I’ll be able to determine with better accuracy. But I’ll hazard an early guess that it is indeed possible.

RV Holding Tank Removal

I need to remove my black holding tank off of a 29-foot Class C motorhome with a slideout. How do you remove the RV plumping from tank? One RV person tried telling me you have to bust it out and replace it with a new tank. This make no sense to me. What can be done and how do you do it? Crawford O. (Dandridge, TN)

Crawford, I'm thinking your RV person is not familiar with the NFPA 1192, Standard for Recreation Vehicles. According to the code, all holding tanks must be removable. That alone, does not mean it’s an easy job. It simply requires manufacturers to make it possible for the tanks to be removed even if it means removing other components first. I go into detail about the procedures in my RV Owner’s Handbook. Unfortunately, it’s too much information to include in an email response, but be assured, it does not have to be busted out piece by piece. 

First verify that the tank actually requires a total replacement. Plastic holding tanks can be successfully welded if cracked. Only when completely destroyed or damaged beyond repair does it actually need to be replaced. I'd "remove and replace" only as a last resort. Here's the bottom line if it does have to come out...

The tank vent and toilet drain enter the holding tank from the top and the drain outlet exits at the lowest portion of the tank. In some cases, the vent can be cut with a hacksaw or disconnected from inside the cabinetry. The toilet simply unbolts from the floor flange, then the flange (which may be connected to the tank in a variety of ways), is simply removed from the top of the tank. The same for the drain outlet on the holding tank itself. It will ultimately terminate and connect with the other holding tank at a location near the left rear side of the coach. All termination valves are removable so you simply remove that pipe and valve associated with the tank in question and reverse the process for installation.

Wish I could provide more clear-cut instructions, but without seeing the actual installation it’s nigh impossible to respond fully. But I hope this little bit will help! 

Frustrating Fly 'Festation' with RV Toilet

I just purchased my first ever motorhome earlier this year, a used 38-foot Damon. I have what seems like fruit flies breeding in the black water holding tank. No problem with the gray water holding tank. Whenever you push the flush foot pedal, the flies come swarming up out of the commode. I tried a half gallon of ammonia down the toilet and it seemed to help for a few days, but to no avail, they are back. I have talked with some of other motorhome residents in my park, but they have never heard of this problem. I usually dump both tanks when they are about two-thirds full. Has anyone had this problem before and what was the solution?
Jim, (San Antonio, TX) 

First off, Jim, congratulations on the purchase of your first-ever motorhome! I’m sure you’ll rack up plenty of RVing miles in the coming months! About your bugs, you are evidently experiencing an onslaught of sewer flies, also called drain gnats among other names, (some of which may not be printable here). Depending on your specific variety, the scientific name is probably either Psychoda alternate or Psychoda cinerea. They are sometimes found in RV holding tanks since they thrive on moist organic waste, especially solid waste. Just the kind of stuff you’d find in the black holding tank. Primarily one that has not been cleaned, flushed or maintained adequately. Chances are, at some point, your new-to-you motorhome was probably stored without the holding tanks being flushed, cleaned and emptied completely.

Thankfully sewer flies do not bite, but they can be very annoying and still even dangerous at times. Because they are born among decaying filth and waste, they have the capability to transmit diseases to humans. Prolific little creatures, they lay their eggs in masses of anywhere from 10 to 200 groups, according to one report I researched. The larvae resemble small worms; basically without legs. The eggs can hatch anywhere between 32 to 48 hours. They mature in about two weeks and simply keep reproducing until they die or are eradicated. But keep in mind, new adults keep emerging from the pupae every 20 to 40 hours! The adults live approximately two weeks.

For short term relief, published reports recommend using a spray can of an insecticide containing pyrethrins or resmethrin. This will knock the adults down for a while. I must admit, however, I’ve never personally tried the insecticide route, but if you do, always follow the proper safety precautions for pesticide use, especially inside the motorhome. After killing those in the immediate area, be sure to sufficiently vent the entire RV. Read the precautions on the spray can carefully! But the best defense against long term infestation is to simply keep the holding tanks flushed and clean during periods of non-use. In your particular instance, it may be necessary to have your holding tanks hydro-cleaned, (see allprowaterflow.com). Because dried out waste can often stick to the bottom of the holding tank or clog the outlet of the tank, simply draining and flushing with fresh water may not be enough to dislodge all contaminants. And as you flush the toilet, the added moisture imbues new life into the larvae, prolonging the infestation. The bottom line is that the toilet drain and the black holding tank must be thoroughly cleaned prior to placing the motorhome in storage.

Though some people may not favor a holding tank additive, the proliferation of sewer flies is one strong case to indeed employ one. An enzyme-based, formaldehyde-free additive, one that helps digest the solids, is my recommendation. I’ve personally seen an infestation so severe that the flies had backed up into the integral tubing inside the toilet. The toilet had to be completely disassembled, cleaned and reassembled. It was quite time consuming. Hopefully your situation isn’t that bad. But it does mandate at least a complete inspection of the toilet and other components such as the vent pipe for that holding tank. It’s not the end of the world obviously, but it is quite annoying!

Rubber or Wax RV Toilet Seal?

I am replacing the closet flange seal under the toilet in my coach. I need to know the way the seal goes in. Does it sit in the flange ring on the floor? Or do you first fit it around the toilet horn? The old seal was just sitting on top of the floor. Is that the right way? Should I use a wax seal? Ed, (West Valley City, UT) 

Ed, I recommend a rubber seal instead of the wax ring type of seal; here's why. During the hot summer months, it’s possible the toilet mounting can become loosened as the wax ring softens. Re-tightening the toilet mounting bolts will help, but the thickness of the wax seal will be greatly reduced with each tightening. With a rubber foam seal, simply slip it over what you call the plastic horn on the bottom of the toilet. If you just place it on the floor flange it’s likely to become dislodged while lowering the toilet into place over the closet bolts. It should easily stay attached to the bottom of the toilet as you lower it into place. 

However, I have seen some rubber flange seals constructed large enough to actually slip over the flange bolts and stay centered on the flange itself. In this case, the bolts can hold the seal in place as you lower the toilet. But to be safe, I recommend the rubber seals that actually fit between the flange bolts and attach to the toilet. Just my preference, however; your mileage may vary!

Slow Flow No Go

I have an Innsbruck and all of a sudden water will not flow into the toilet. We do use a filter for all the water coming into the camper. It is a little slow in the sink and shower, too. I did clean the screens at each faucet. What else can I do?
Bill, (Keithville, LA)

Bill, it is quite possible the filtering media in the filter you are using has been saturated beyond its usefulness. Oftentimes filters become clogged and must be replaced with a new insert. Some have replaceable cartridges while some must simply be tossed out and replaced with a complete new filter. Not knowing which filter you are using, I would indeed at least start there.

Does the problem persist whether you are using city water or the on-board system with the pump or both? If the problem exists only when operating the water pump, look for another filter on the input side of the pump between the tank and the pump. Oftentimes, particles inside the water tank can become lodged in the pump filter or in the pump itself. If it happens while on city water also, look for a kink or sharp bend in the supply tubing at or near the city water inlet inside the coach.

It's also quite possible the fresh water line is blocked at the toilet inlet valve or that the valve itself may have been rendered faulty. Try this; with the water source disconnected or turned off, remove the tubing right at the toilet. Have a large pan at the ready then have an accomplice briefly turn the water pump on. If water exits the tubing at the toilet, it would prove a faulty inlet valve on the toilet. 

Purposeful RV Toilet?

Some RVers have told us that RV toilets should never be used for bowel movements but only for liquid waste. This seems very inconvenient. Could you please set us straight?
R., (Cowansville, PQ, Canada)

Obviously some RVers are a little whacky R.! It’s a toilet and can be utilized as such. That’s like running the generator and not allowing the air conditioner to operate, or having a refrigerator, but not allowing food storage in the freezer, or like having a range, but only using the top burners and never the oven. Okay, so it’s somewhat similar anyway! But like anything RV, maintenance is required, along with conservation to some degree; especially while dry camping. Some RVers only use RV approved toilet tissue. Personally, I’ve never found this necessary if proper precautions are taken. Standard procedures such as regularly rinsing and flushing, using an enzyme-based additive (not a chemical), having an annual hydro-cleaning and only dumping the holding tanks when they are over 3/4s full.

Overfull Flusher

My toilet in the RV seems to keep filling up after it has been flushed, to the point of filling the bowl up over a period of time and running over the toilet. How do I fix it?
Tammy, (Iowa Park, TX)

Tammy, there is likely a problem with the toilet inlet water valve. The most common is called a “ball valve”. Either the valve is leaking or it is not closing completely; possibly as a result of the flush mechanism binding. Activate the flush mechanism several times and make sure it is not binding or sticking. Be sure it has freedom of movement and returns to its fully closed position. If you can, reach behind the toilet to where the flush linkage connects to the water valve and manipulate the mechanism directly attached to the valve. If you are able to feel extra movement then the valve is probably not fully closing. It could be partially blocked by mineral contaminants in the fresh water. It’s actually better to remove the toilet from the coach in order to gain full access to the mechanism and water inlet valve. If the flush mechanism is not binding and the water valve appears to be fully closing, then it is likely leaking internally and you can simply replace the entire water valve. Replacement parts are conveniently available for most all RV toilets at any RV parts store.

Illuminated Holding Tank

I dropped a plastic flashlight into the toilet and it went straight down the pipe to where I could not see it. The reason I was using a flashlight was to determine what might be causing a backup in my black water holding tank. Now I apparently have two problems. I can back flush the tank with the attachment on the drain and also force water down the toilet from that end to eventually get things cleaned out. The pipes are all glued and therefore not easily removed to get to the possible plug. Do you have any ideas how I might be able to extricate a plastic flashlight which is probably lodged in a 45 degree turn going into the black water tank?
Sherman, (Logan, UT)

Sherman, I'm guessing the drop of the flashlight resulted in it going straight into the tank itself. Most configurations have the toilet positioned directly over the tank with a straight pipe into it. There are a few floor plans which mandate an elbow turn, but unless that was one big, honkin' flashlight, it probably entered the tank. 

The good news is that all holding tanks must be removable. Though tank drain pipes connections are usually cemented, the assembly can easily be cut apart if necessary. The termination valves are bolted between two adapters so it may be possible to simply unbolt the valve assembly, remove the toilet and flange from above, then remove the attaching brackets to drop the tank. Obviously it's best to flush the tank as good as possible first. Once the tank is down, you should be able to manipulate the flashlight to the three-inch outlet opening and retrieve it. Though a hassle and not very pleasant a task, it is doable and not that bad a situation. Once dropped (the tank that is), you can then, more easily, inspect the tank to determine the cause of the first blockage. Oh, and be sure to change those batteries in the flashlight!

Bus Toilet

I'm building my own motorhome from a bus. I’ve read lots of details, but why can't I just install and plumb for a residential toilet rather than a fancy-dancy marine or RV toilet? What's the big deal?
Randy, (Magnolia, TX)

Randy, there would be no physical problem installing a household-type toilet in a bus conversion. Many custom builders do. The main reasons mainstream production RVs utilize the RV marine toilet is for efficiency and weight reduction. The RV-specific toilet is much lighter in weight and uses much less water. In some RVing circles, conservation of resources is crucial; a toilet that flushes with less water is most beneficial, especially in a dry camping situation. Plus a marine toilet will not fill the holding tank as rapidly as a residential toilet. Compare the amount of water used per flush between a residential toilet with a standard back-tank and a newer, more efficient marine toilet. It’s doubtful the weight factor will be an issue on a bus chassis, but typically RVs are constructed with the overall weight issue high on the list of priorities. Not only the weight of the heavy porcelain in a household toilet, but the weight of the water you will be carrying around in the back-tank is also a consideration. Both types mount identically with a typical floor flange so it is doable. If it’s purely the bone china finish you are seeking, there are some nice porcelain RV toilets available now that will fill the bill.

Toilet Replacement

How would I install a new toilet in my RV? I’d like to go to a bigger one. Is the RV toilet the same as a toilet in a home with the two bolts and the wax ring? Or is it an entirely different hook up?
Armin, (Tacoma, WA)

Armin, the RV toilet differs from a typical house toilet in that it does not have a back tank. As you know, coach owners must conserve all resources so RV toilets are designed without a back tank in order to conserve water. They flush using very little water comparably. The good news is that they all mount to the floor flange in the same manner with a couple of exceptions. Some RV toilets utilize four mounting bolts instead of the usually two. And some two-bolt installations have the bolts positioned at 11 and 5 o’clock instead of 9 and 3 o’clock. Adapter kits, however, are available that make RV toilet installations simple for most handymen.

There are many RV toilets on the market; take a look at any accessory store for an assortment of sizes and styles. I personally favor those made from porcelain instead of the usual plastic. They have the look and feel of a standard house toilet, sans the back tank. As a suggestion, check out the Magnum Opus RV toilet, developed by Dometic. It is constructed of 100% vitreous china. RV floor flanges are identical to most modern homes but rather than a wax ring, I recommend a rubber seal to eliminate the possibility of heat softening and distorting the wax ring, thereby, loosening the toilet. This situation isn’t common with houses, but could be with motorhomes.

RV Remodel

This may be a common problem other older trailer owners are facing. We bought a second-hand fiberglass Burro trailer which we are very happy with but would like to upgrade the trailer to include a toilet and shower with a black and grey water system. The manufacturer has gone out of business so we have called the two other competitors of small fiberglass trailers, Scamp and Casita to see if they could retrofit the toilet and shower. They stated they would not be able to do so. Do you know of anyone who does custom retrofitting or where we can buy supplies and obtain information to do it ourselves?
Frank, (Globe, AZ)

Frank, though difficult, retrofitting an existing RV can be accomplished in many cases. The problem with the smaller units is space limitations, especially when installing plumbing vents and drains as well as the holding tanks. It would require a thorough inspection to determine if such additions are even possible on your unit. Try to find companies that specialize in RV modifications, commonly they are referred to as RV decorators. Also contact van converters for their opinion as well. Most any competent, full service RV repair facilities should also be able to evaluate your situation.

Unfortunately, I’m not aware of any RV decorators in your area. All the parts and supplies, however, should be easy to gather from sources including Home Depot, Lowe’s and standard RV accessory stores. The holding tanks and RV toilet can be purchased at any RV supply house, but common ABS drain and vent piping as well as all the fittings and solvents are available at any of the big box home improvement stores too.

Flustered Flushing Folly

We just purchased a clean older RV and have discovered a leaking plastic toilet. The toilet leaks from the top back when the "flush pedal" is in operation. If the toilet's not flushing, there's no leak. Any suggestions?
Joanne, (Sewell, NJ)

Joanne, the symptoms you’ve indicated point to a faulty vacuum breaker assembly in the upper reaches of the toilet. At the age of your motorhome, I’m guessing it is probably a Thetford Aqua Magic or an earlier version of that toilet. Repair parts are still readily available at any well-stocked RV parts store. The toilet will have to be removed from the coach for the repair, but the actual parts replacement is relatively easy if you are handy with common hand tools. I would recommend replacing all the seals in the toilet also since you will have the toilet out of the RV during the repair anyway. Again, the seals and the vacuum breaker assembly are fairly easy to replace, albeit a little messy (I always wear latex surgical gloves when working on any waste system component). Each kit will come with definitive how-to instructions.

After obtaining the correct parts, begin by turning off the water supply (water pump and city water) to the toilet and bleed the pressure by flushing the toilet one last time. Remove the water inlet line at the rear of the toilet; it’s usually best to plug or cap that line while the toilet is removed. The toilet is held to the floor flange by two closet bolts positioned at about 11 and 5 o’clock when facing the toilet as installed. To gain access to the front (5 o’clock) bolt, depress both foot pedals; you’ll be able to get an end wrench in there fairly easily, but a ratchet wrench actually works better if you have one. An off-set ratchet wrench works the best. The back bolt can be accessed by reaching behind the toilet or by removing a knockout plug located under the seat at about the 11 o’clock position. A socket extension and universal joint will most likely be needed if approached in this manner. Once you remove the two closet bolt nuts, simply lift the toilet up and over the bolts and take it outside. Place the toilet upside down on a workbench with the rear of the toilet facing out. You’ll now be able to see all the innards inside the toilet casing.

Read and follow the replacement instructions as written for the vacuum breaker and the seals. Reinstall the toilet in the coach by reversing the above steps. Connect the water line, apply water pressure and check for leaks. Not a pleasant task for sure, but one easily accomplished by the handy do-it-yourselfer.

Toilet Tube Troubles

I have a Sportscoach III on a P30 chassis. I need to either shorten or modify the 3-inch down tube connecting the toilet to the black water tank. The problem is that the tank is oddly shaped because part of it sits over the tag axle and is very shallow. Unfortunately that is exactly where the waste dumps from the toilet. The result is that the tube ends about 1-1/2" above the bottom of the tank (short section). Because the tank never fills to this level, even when full, the tube plugs quickly and virtually every time it is used. So, I need to either add an elbow to the down tube or cut it off flush with the tank bottom. But how do I get the tube out of the tank? Does the flange unscrew? Or is it glued directly to the tank?
Mark, (Portland, OR)

Mark, indeed it is a shame when a floor plan dictates the location of such fittings with a negative result. It just so happened that the floor plan mandated the toilet be positioned over the tag axle on your rig. Most 3-inch toilet drains flow straight into the holding tank. Unfortunately, yours dumps right onto that "shelf" at the shallow end of the tank. Toilet drains may be diverted to a location further over on the top of the tank, but it requires enough clearance for three, 45-degree turns in the ABS pipe. Never use a 90-degree elbow for the toilet drain. This is possible only if you have enough vertical clearance between the bottom of the flooring and the top of the holding tank to position the three 45-degree elbows and the necessary connecting pipes. To be sure, purchase short-turn, 45-degree elbows and lay them out on the floor and measure the minimum height required. 

The toilet and the floor flange must be removed in order to drop the holding tank. Also, the termination assembly and the vent pipe must also be disconnected from the tank before it can be removed. Some flanges and toilet drains are glued, some are threaded and some use a simple friction seal with the downpipe inserted into a rubber grommet at the top of the tank. The downpipe should never extend into the holding tank more than three-quarters of an inch. Extending further into the tank is only possible with the rubber grommet even though there is a lip on the inside of the grommet. Remember, it is only rubber, so a "too long" pipe can be pushed past the lip and forced further into the tank. This may be what happened on yours. If your downpipe is threaded or cemented, it cannot extend too far into the tank because the threads and the seat of the fitting would limit its travel. 

First remove the toilet and then the screws holding the flange to the floor. Try to "unscrew" the flange and downpipe together as one unit. (A simple removal tool can be made by using a short piece of 1 X 3 shelving material with two 3/8-inch holes drilled through it that match the spacing between the two existing closet bolts in the flange. 

After the toilet has been removed, place the board over the closet bolts and rotate counter-clockwise). If it will not rotate it is probably cemented. If cemented, the drain pipe will have to be cut between the bottom of the floor and the top of the tank. If you have the rubber grommet or the threaded fitting into the tank, the flange and downpipe assembly will twist free and can be removed from inside the bathroom. 

Careful measurements can then be made to determine if the pipe extends too far into the tank and/or if you have the needed space to install the 45-degree ells to move the inlet to a deeper section of the tank. If you have the clearance for the 45-degree fittings, then you can drop the tank, cut a new opening in the tank and have the old inlet plastic welded with a patch. Check to see if your local RV shop indeed has a plastic welding unit. Welding will be the only way to guaranty a leak-free patch. 

Then reinstall the tank using the 45-degree elbows; connect the termination assembly and vent. Be sure to fill the tank with fresh water all the way up and into the toilet bowl to test the integrity of the modification.

Failing Flange

I have a question regarding a toilet flange. The flange that holds my toilet down has rotted away and will NOT hold the bolts in place; those bolts of course being the ones that secure the toilet. I already told a service technician to fix it but he quoted me a semi-high price also saying the holding tank might need to be dropped to remove the flange. Is there an easy do-it-yourself fix or should I just bite the bullet and let him repair it? I don't feel right telling him not to after I told him to do it. However, I would like to know the process it takes to fix something like this so I can question him. It's an Aqua Magic toilet in a 1991 rig.
Chad, (Acton, ME)

Chad, the modern toilet flange is typically made of ABS plastic so it’s doubtful that the flange itself has rotted away. More likely, the floor has sunk around the flange. In any event it will be necessary to remove the toilet and inspect the floor and the flange. It may not be necessary to remove the holding tank in order to remove the flange. In fact, just the opposite is true; it is absolutely necessary to remove the flange before the holding tank can be removed! It should take no longer than one hour to remove the toilet, inspect the flange and floor and make a determination as to what repairs are necessary. Toilet flanges/downpipes are either threaded into an adapter secured to the top of the holding tank or cemented using ABS cement. Others may just slip into a rubber grommet attached to the tank. The inspection mentioned above will reveal exactly how your flange is attached.

In rare instances it may be necessary to drop the holding tank to make the repair, but quite often the flange can be replaced from inside the bathroom only. The closet bolts which hold the toilet to the flange may simply be loose. I’d recommend tightening those nuts first. You may have to lift up on the toilet while tightening the bolts to keep the base of the closet bolts in place. But if the bolts indeed pull through the flange, it will have to be replaced. If the toilet fits securely to the floor after tightening, then the flange is probably okay and just the seal between the toilet and the flange needs replacing. I’ve seen wax flange gaskets soften in the summer due to excess heat. This will indeed make the toilet loose on the flange. Replace wax gaskets with a rubber flange seal. But obviously this is all speculation until the inspection. If a rotted or sunken floor exists, then more extensive repairs will be in order.

Seepin' Toilet Seal

I have a question about RV toilets. The one in our older motorhome seems to work fine but I'm wondering if the valve is closing properly. My neighbor says that the toilet should hold water in the bottom bowl to make a seal to prevent odors. All the water leaks out of mine and into the holding tank. I cannot find anything that may be preventing it from closing completely. Is this a do-it-yourself repair or do I need a professional?
Harv, (La Crosse, WI)

Harv, indeed, there should be some water left in the bowl after every flush. Without the water seal, odors from the holding tank can and will enter the coach. There are a few possible reasons for the water to leak out; first, check to be sure that the bolts which secure the toilet to the flange are not too tight, thereby distorting the base of the toilet. If the toilet is mounted on top of carpeting, trimming the carpet so the base rests solidly on the floor is best. If the base is too tight, the flushing mechanism will become warped or wracked and not close fully.

But the most common cause is simply that paper and waste have accumulated inside the slide valve mechanism on Thetford’s Aqua Magic units. On an older SeaLand toilet, the typical cause is a worn seal or a clamp ring that is too loose. Yours is likely to be one of these two brands.

If you have an Aqua Magic, fashion an L-shaped hook out of a coat hanger or a bent screwdriver that will reach into the groove to scrape out the residue. Turn off the water supply, depress the flushing pedal and carefully remove any paper jammed into the groove just below the rubber seal. There is a tool you can purchase from Thetford just for this task if you wish. Take special care not to damage that seal. In severe cases, the toilet will have to be disassembled and the flushing mechanism taken completely apart, then cleaned, lubed and reassembled.

To rectify the situation on the SeaLand toilet, simply tighten the clamp ring. In some cases, a complete seal kit may have to be installed if water still continues to seep past the seal and into the holding tank.