Thursday, July 7, 2011

Toilet Trouble-Shooting

A common complaint with RV toilets is that the seal in the bowl valve often fails to hold water in the bowl. Sometimes with a little preventive maintenance, the onset of this problem can be slowed. Here are some suggestions:

Problem: Bowl doesn't hold water.


- Periodically dump a small amount of holding tank valve lubricant into the bowel and let it stand. It will lubricate the seal.

- Another suggestion is to pull 3/4 of the bristles out of a toothbrush and brush some silicon grease onto the seal. Obtain the silicon lubricant from ACE hardware. It is in a 1.5 inch dia. plastic container, one inch high for $5.

- Purchase .040 screen spline used to hold the screen in the screened door, cut to length and wedge it between the rubber gasket and the bottom of the bowl. Form it into a circle and place it on top of the existing gasket. You're adding a second, softer gasket.

- First shut off the water pump and hold the toilet's flush (ball) valve open until all the water drains out. Then, with the flush valve closed again, add about a cup of undiluted white vinegar. (The water pump can be turned back on at this point, so you can use the sinks and shower.)     After letting the vinegar sit for a couple of hours (replenishing as necessary to keep the valve covered with vinegar), pour in a few tablespoons of baking soda, and scrub the bowl with a toilet brush. The baking soda serves two purposes: first, it's a mild abrasive that helps remove any remaining mineral deposits that the vinegar has loosened; and second, it neutralizes the vinegar's acidity, so that you don't kill off the beneficial bacteria in your tank. Then flush the toilet and repeat the baking soda treatment, until the contents of the bowl no longer foam, at which point you'll know the acidity has been fully neutralized.     Give this simple procedure a try before you resort to more drastic measures or call in expensive professional help.

- Read the LD Companion article on Toilet Bowl Seal Replacement.

Problem: Water drips from rinse hose and/or water around toilet base.

- The likely culprit is the vacuum breaker.  The part is difficult to get to - it may be just as easy to take the toilet apart and install new parts for the replaceable items, such as the vacuum breaker, toilet seal, flush ball and water valve.

- Getting to the parts, aka removing the toilet: there is a cosmetic fitting on the bottom of the toilet that is held on with a small Phillips-head screw. You must remove this see where the toilet fastens to the floor. The four common places for leaks are the flush valve on the left side of toilet, the vacuum breaker on rear top of toilet (you'll need to remove toilet to get to it), the middle Telfon ball seal valve (top half of toilet must be removed to replace), and the flange base seal where the toilet bolts to the floor.

- For more info on replacing these parts, read this article:

Problem: Water won't stop running into bowl when you release the flush/fill pedal.

Solution: Probably the water valve is worn and is getting stuck in the 'on' position. It is a common part and should be available at any RV dealer's Parts Counter.

There isn't enough access room to change the valve in place, so the toilet will need to be removed. Do the installer a favor and make sure the black water tank is empty and has been flushed first. Summer is a miserable time to work on or near open holding tanks;-)

- Removing the pedestal cover: There are two screws on the inside of the "pedal".  Remove them and you will have better access to the pedestal cover which snaps off if you have the short base and has one screw for the tall base.

While you're at it, to avoid problem 1 above, it might be a good time to change the bowl seal, if it has been more a than a few years since the last replacement.

Problem: Clogging issues with the Mid-Bath toilet.

Solution: Read the LD Companion article on the Mid-Bath Toilet Problem.

Problem: Can't add water by pulling pedal up.

If you can get down low in front of the toilet and look inside of the plastic cover that is at the rear of the pedal, look for the following.  There is a plunger with a plastic mushroom shaped top that activates the water valve below.  There is a curved medal rod inside the pedal's shell.  When you push down on the pedal, this curved rod should depress the plunger (and yours appears to work in this direction).  When you lift the pedal, the same curved rod should also cause the plunger to be depressed.  I'd guess the curved rod in your pedal assembly is either bent or broken.

Problem: Have to push pedal down before it can be pulled up.

It's possible that the toilet's spring cartridge is mounted too tightly. To access the two mounting screws, here's what you need to do:

1. Unsnap the plastic shroud on the toilet's base. It's hinged on the right side and snaps together on the left, by the pedal. Shove a screwdriver in there and pry it open--it's pretty sturdy, so you're not likely to break it. (Even if you did, it would be no big deal, since you can reassemble it without snapping that side together and it'll still look OK.)

2. With the shroud out of the way, you can get a Phillips screwdriver in and remove the two screws on the inside of the plastic pedal. They're a bit recessed, but easy to see. A stubby screwdriver works best.

3. Once the screws are out, you can remove the plastic cover plate they hold in place, and then slide off the big plastic pedal cover.

Now, looking from the left,  you should be able to see the business end of the water valve assembly. Try loosening the two screws that hold it in place a quarter turn and see whether that solves the problem. If not, back them off another quarter turn and try again.

Also, it doesn't hurt to shoot a little silicone spray at the base of the mushroom-shaped valve actuator--the place where its shaft slides into the valve assembly.

Contributors: Larry Wade, Bill Atkins, Roger Nickey, WxToad, Bob Moore, Ric, Jim C., Art, Andy Baird

Revised: 11 May 2014