You should change the diaphragm and adjust the screw to get the proper flush cycle. See the instructions, or look online for them.
A Sloan Valve is used primarily on toilets. The Sloan Valve is the device that allows one's toilet to flush normally and properly, releasing all of the water at once.
Kelly Sloan
A sloan valve is a valve used for a toilet or sink. Unless you have a bathroom in you car there is no way you need a sloan valve for your vehicle.
Sloan Valve Company was created in 1906.
The population of Sloan Valve Company is 1,000.
Sloan urinal flush valves operate using a diaphragm mechanism that regulates the flow of water to the urinal. When the user activates the flush handle or sensor, the diaphragm opens, allowing water to flow from the supply line into the urinal. Once the flush is complete, the diaphragm returns to its closed position, stopping the flow and conserving water. These valves are designed for efficiency, often using a preset volume of water for each flush.
A "Sloan Valve" is the well known valve used on (primarily) commercial toilets and urinals. Touching the chrome handle causes the toilet to flush, violently washing your troubles down the drain. What does that handle do and what makes the toilet flush with such great force? If you look closely, the pipe coming into the valve is much larger in diameter than an ordinary toilet's pipe. This is the secret to the Sloan Valve. The normal water pressure in the building pressurizes the big pipe and when the famous chrome handle is moved, the water in the big pipe is allowed to dump all at once into the toilet. When most of the water pressure in the big pipe is depleted the chrome handle resets and the water stops flowing. If the toilet had a small pipe like most other toilets, the large water volume would not be possible, and the high power flush that we have all grown to love would not be possible. So, the Sloan Valve is not the secret at all. It's the large pipe ahead of it that stores all the water and it's associated pressure. The Sloan Valve is just a large valve capable of releasing it all at once.
The sloan valve is the best valve available to put on a toilet. If you have a toilet that is used a lot, you should definitely get one.
The link below will answer all questions.
Some are NOT be removed such as Sloan Royal
You can purchase a replacement flush valve in every do-it-yourself store or you can call a plumber, who can replace the old flush valve and install the new one.
To troubleshoot and replace a malfunctioning toilet tank flush valve, first turn off the water supply to the toilet. Remove the tank lid and inspect the flush valve for any visible damage or debris. Clean or replace the flush valve if necessary. To replace the flush valve, disconnect the water supply line and unscrew the old valve from the tank. Install the new flush valve according to the manufacturer's instructions and reattach the water supply line. Turn the water supply back on and test the flush valve to ensure it is working properly.