Toilet keeps on running

SOURCE: Possible toilet leak or doesn't stop running...

this sounds like the ballvalve needs replacing & the hissing is the sound of water as the valve is not shutting off properly.
The valve at the bottom of the tank is possibly just a half turn valve so try that & see if it stops the water.
The water leaking could be thatthe water level is too high & leaking around the handle assembly & running down, so it kinda looks as though its leaking below?
The handle assembly may of come adrift so thats whay the handle may look loose ?

Solution sounds quite straight forward, a new ballvalve assembly needs to be fitted & the handle assembly sorting.
The leak will be rectified when you replace the old ballvalve, as you will need to turn off the water to the unit to remove the ballvalve, whilst the water is off a service valve should be fitted so as any future probs or servicing needs doing then it can be isolated without the need for turning the whole house off?

This work should be carried out by a registered plumber & is as i said a straight forward job.Price approx £65.00 subject to a survey by the plumber.

I hope this has helped

kindly

Richie

SOURCE: Running water in Geberit Starck Toilet

I hate to say it but you may need a pro on this one, if you want I can try to walk you threw it but let me know. [email protected]

SOURCE: Water continues to pour into the overflow tube at end of cycle

I am also on a well and had what sounds like the same problem, so I contacted Toto tech support at [email protected].  They responded within 24 hours with information which enabled me to successfully resolve the problem.  
Basically, they provided a set of diagrams and instructions which enabled me to take apart the flush valve, clean it, and reassemble it.  It took less than 15 minutes, and cleared up the problem immediately.
By-the-way, those instructions also mention an annual cleaning of the flush valves, which might well prevent future problems.  A filter to remove debris from the water supply is probably a good idea, too.

SOURCE: Toilet won't stop running

I have a Kohler toilet and Ingenium fill valve 85297-AA. My toilet kept running, the fill valve black cylinder wouldn't pop up and when I added blue food coloring to the tank, the blue color seeped through to the toilet bowl. First I replaced the flapper and that allowed the fill valve piece on the cylinder to pop up correctly and blue dye no longer seeped through to the bowl. I still heard a hissing sound when the toilet tank had filled and no water was going into the overflow tube. I called the tech support number on the Kohler website 1-800-4KOHLER (1-800-456-4537) . Here's what solved the problem: Turn off the water to the toilet.Take off the white cap of the fill valve by pushing it down and turning it counterclockwise as you would open up a childproof pill container. Then unhook the metal hook. Hold a cup upside down (I used a strong plastic cup) over the part of the fill valve that is left in the tank and turn on the water. (You need the cup because otherwise the water will squirt up to the ceiling.) The water will flush out the fill valve. Replace the cap and the hook and flush.

SOURCE: running toilet

your float is stuck