Introduction
This manual provides essential information for the proper installation, function, and care of your Kohler K-1097741 Diaphragm Assembly. This component is a critical replacement part designed to restore the efficient flushing operation of compatible Kohler toilets. Please read these instructions thoroughly before beginning any installation or maintenance.

Image: The Kohler K-1097741 Diaphragm Assembly, a small, circular rubber component essential for toilet flush valve function.
Safety Information
Always observe the following safety precautions when working with plumbing fixtures:
- Turn off the main water supply to the toilet before starting any work.
- Wear appropriate personal protective equipment, such as safety glasses, to prevent injury.
- Ensure the work area is well-lit and clear of obstructions.
- If you are unsure about any step, consult a qualified plumber.
Package Contents
Verify that your package contains the following item:
- 1 x Kohler K-1097741 Diaphragm Assembly
Setup and Installation
Follow these steps to replace the diaphragm assembly in your Kohler toilet:
- Turn Off Water Supply: Locate the shut-off valve on the wall or floor near the base of the toilet and turn it clockwise until the water flow stops completely.
- Empty Toilet Tank: Flush the toilet to drain most of the water from the tank. Hold the flush lever down until the tank is as empty as possible. You may need to use a sponge or towel to remove any remaining water.
- Remove Tank Lid: Carefully lift the toilet tank lid and set it aside on a soft, stable surface to prevent damage.
- Locate Flush Valve: Identify the flush valve mechanism inside the tank. The diaphragm assembly is typically located at the base of this mechanism.
- Remove Old Diaphragm: Depending on your specific Kohler flush valve model, the diaphragm may be held in place by clips or a twist-lock mechanism. Carefully detach the old diaphragm assembly. Note its orientation for correct installation of the new part.
- Install New Diaphragm: Position the new Kohler K-1097741 Diaphragm Assembly into the flush valve. Ensure it is seated correctly and securely, matching the orientation of the old part. It should fit snugly without being forced.
- Restore Water Supply: Slowly turn the water shut-off valve counter-clockwise to restore the water supply to the toilet tank. Allow the tank to refill.
- Check for Leaks and Functionality: Inspect all connections for any signs of leaks. Flush the toilet several times to ensure the new diaphragm assembly is functioning correctly and the toilet flushes powerfully and refills properly.
- Replace Tank Lid: Once you have confirmed proper operation and no leaks, carefully place the tank lid back onto the toilet tank.
Operating Instructions
The K-1097741 Diaphragm Assembly is an internal component of your toilet's flush valve. Its primary function is to create a seal that holds water in the tank until the flush lever is activated. When the lever is pressed, the diaphragm lifts, allowing water to flow into the bowl. Proper installation ensures efficient and reliable flushing. No direct user operation is required for the diaphragm itself beyond the normal use of the toilet flush lever.
Maintenance
The Kohler K-1097741 Diaphragm Assembly is designed for durability. Regular maintenance is generally not required for this component. However, if you notice issues such as a continuously running toilet, a weak flush, or a toilet that fails to flush, the diaphragm assembly may be worn or damaged and require replacement. Inspect the diaphragm for cracks, tears, or deformation during troubleshooting.
Troubleshooting
| Problem | Possible Cause | Solution |
|---|---|---|
| Toilet runs continuously or cycles on and off. | Diaphragm is not sealing properly, is worn, or is misaligned. | Turn off water, inspect the diaphragm for debris, damage, or improper seating. Re-seat or replace if necessary. |
| Weak or incomplete flush. | Diaphragm is partially obstructed or damaged, preventing full water flow. | Inspect the diaphragm for wear or obstruction. Ensure it lifts fully when the flush lever is pressed. Replace if damaged. |
| Toilet does not flush at all. | Diaphragm is completely failed, dislodged, or the flush valve mechanism is broken. | Check if the diaphragm is properly installed and intact. If the diaphragm is fine, inspect other parts of the flush valve. Replace the diaphragm if it is the cause. |
Specifications
- Part Number: K-1097741
- Manufacturer: Kohler
- Item Weight: 0.176 ounces
- Product Dimensions: 0.01 x 0.95 x 1.55 inches
- Material: Rubber/Plastic Composite (typical for diaphragm assemblies)
Warranty and Support
For information regarding the warranty of your Kohler K-1097741 Diaphragm Assembly, please refer to the official Kohler website or contact Kohler customer service directly. Keep your proof of purchase for warranty claims. For further assistance or technical support, visit www.kohler.com or consult a professional plumber.





