How to Fix a Flushometer which Doesn't Flush

What You'll Need
New rubber cup or diaphragm
Monkey or socket wrench

Sometimes, over time, a situation might develop in which your toilet or urinal flushometer will not flush for one reason or another. If you are confident in your ability to work with plumbing and water, why not skip the frantic call to the plumber and attempt this repair by yourself? Using the steps listed below, you should be able to diagnose and repair this problem without spending money on a professional service call.

Step 1: Turn Off Water

When you are undertaking any project dealing directly with plumbing or water supply, turning off the water will almost always be your first step. Aside from creating a gigantic mess that you will need to clean up, leaking water can cause flooding that can severely damage your home, requiring more money spent to fix this new problem. Additionally, due to high water pressure contained in many water pipes, failure to turn off your water could cause injuries if a pipe bursts or sprays. To avoid all of these issues, be sure to turn off water before continuing onto the next step.

Step 2: Remove Outer Cover

At the top of your flushometer assembly, you will find an outer cover. With either a monkey or socket wrench, unscrew the outer cover and remove. 

Step 3: Remove Inner Cover

Under the outer cover, you will find either an inner cover (in the case of a diaphragm-type flushometer) or a gasket and inner cover (in the case of a piston-type flushometer). In either case, you will need to remove the inner cover. If the inner cover is stuck, use a screwdriver to pry it off.

Step 4: Remove Further Pieces

This next step will vary based on whether or not you are dealing with a diaphragm-type flushometer or a piston-type flushometer. Instructions for both are below:

  • Diaphragm-type: Next, you will need to remove the relief valve and the valve seat. You should be able to remove both of these by hand.
  • Piston-type: With a screwdriver, remove brass screws and the retaining plate found beneath the screws.

Step 5: The Source of the Problem

Finally, after removing all of these pieces of the flushometer assemblage, we have reached the part of the flushometer that will need to be replaced. In diaphragm-type flushometers, this part will be a diaphragm that will most likely appear clogged or dirty. Remove the old diaphragm and replace with a new one obtained from your local hardware or plumbing supply store. In piston-type flushometers, the part that will need to be replaced is a small rubber cup. Again, this cup will appear dirty or clogged and will need to be replaced. This part can also easily be obtained at a local hardware store.

Step 6: Reassemble and Test

After replacing either the diaphragm or the rubber cup, reverse the steps you followed in steps 1 through 4 in order to reassemble the flushometer device. After making sure that the flushometer has been assembled correctly, turn on the water once again and test to make sure the device is now working properly.