How do I Repair a Thetfold Toilet?

Susan Revermann

Thetford manufactures toilets specifically designed to fit into most recreational vehicles (RVs), and has been doing so since the 1970s. You should perform some troubleshooting techniques to identify the issue if you haven't located the source of the problem. Repair the issue or replace broken parts as needed. When purchasing replacement parts, make sure you locate the product identification number to make sure you get the appropriate part for your toilet.

You will need a socket wrench for repairs to your Thetfold toilet.
  1. Open the Thetfold toilet seat and cover. Push back the toilet seat hinges to release the seat.

  2. Look in the toilet bowl and see if there is anything stuck in the toilet blade groove. If there is anything stuck in this area it will not hold water. Clean the blade groove with a toilet brush or Thetford toilet cleaning tool.

  3. Check to see if the toilet will hold water. If it doesn't hold water, examine the bolts that hold the toilet to the floor to see if they are over-tightened. Loosen them, if necessary, in a counterclockwise manner with a socket wrench.

  4. Examine the toilet blade seal. The blade seal is sits along the path of the blade, which slides open and closed when you flush the toilet. If there are any cracks or thinning, you will need to replace the seal. Pull the seal from its position with needle-nose pliers. Put a thin layer of Plumbers Grease or silicone-based lubricant on the seal and slide it into the groove that you removed the old seal from. Never use petroleum lubricants for this as it will damage the seal.

  5. Watch to see if water drips or runs into the bowl. If the water runs more than 10 seconds after you flush, you may need to replace the water valve. The water valve connects the water supply to the back of the toilet. Turn the water supply off first. Disconnect the water supply hose from the valve, use an adjustable wrench to unscrew the valve in a counterclockwise manner and screw in the replacement valve in a clockwise direction.

  6. Remove the Starlite and Aqua Magic Galaxy toilets by first turning off the water supply. Remove the mounting bolts and nuts where anchoring the toilet to the floor. Push down the foot pedal to access the bolt and nut behind it. The other is behind the toilet. Lift the toilet seat and cover up, then find and remove the hole cover on the upper side of the hopper. Pull the water supply line from its connector and pull the toilet from its position.

  7. Remove the Aqua Magic IV toilet by finding and disconnecting the water supply line from the back side of the toilet. Look on both sides of the toilet and remove the nuts that hold it in place. Pull the toilet up to remove it.

  8. Look behind the toilet to see if it is leaking there. If you have a Thetford Aqua Magic IV, you will need to replace the water valve (see step 5). Otherwise, this will indicate that the vacuum breaker needs to be replaced on the Thetford Galaxy, Starlite, or Aqua Magic Aurora toilet models. The vacuum breaker makes sure the water flows only one way into the toilet. Remove toilet completely from RV and pop the seat off. Detach the vacuum breaker from the back of the toilet by squeezing the locking tabs together that hold it in place. Pull it away from the toilet unit and replace it with a new vacuum breaker. Put it back together in the reverse order.

  9. Look under the toilet seat rim of the Aqua Magic IV for the product identification number. Look above the back of the toilet seat on the Aurora, Starlite and Galaxy models. You will need this ID number to buy replacement parts.