Wednesday, November 29, 2023


Possible fixes for hard-to-reach toilet leak

Dear Gary,
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.

Dear 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 (photo) 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 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 to 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.

gary-736Read more from Gary Bunzer at the See Gary’s videos about RV repair and maintenance.





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Craig T (@guest_41801)
4 years ago

I too had the same issue. The parts kit came with the seal floor seal because it assumed that you had to remove the toilet to replace the valves. It was tight but I was able use a mirror and replace the parts. I would suggest that if your hands are too large, maybe find someone with smaller hands that can do the job if you don’t wish to remove and replace the toilet.

impavid (@guest_41531)
4 years ago

My toilet was leaking from the vacuum breaker. I couldn’t get the part right away so I sealed it with hot glue. This fixed the problem and the toilet operated just fine. I bought a replacement but never did install it.

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