Fluidmaster Dual Flush Valve S2DBL won't flush.

First shut water off at stop than flush all the water out of the tank next take a sponge and get all the water out of tank next unsrew the supply line from the valve under tank than move out of the way next unsrew the nut on the valve of fluidmaster than pull the fluidmaster out of tank stick the new fluidmaster in tighten nut srew the supply line back on turn on stop and let the tank fill up thats it if the fluidmaster dont shut off press the handle let some water out and adjust the fluidmaster screw Tip the water should stop a 1/4 inch below the flush valve tube in center of toilet

Just replace the flush valve with another one.
Flush the water line by opening valve before attaching new flush valve

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if the fluidmaster,itself is leaking, there is a rubber disk in the base of fluidmaster, replace disk. however, i can almost promise you the dripping you hear is from a bad flapper. replace with KORKY brand flapper. buy the basic black one, with no water saving gadgets on it.you will see cheaper black ones, but get the KORKY

What setting.get are you speaking of? If its the water level you can adjust that by the screw on the side of fill valve.

turning the water shutoffs off and one can cause debris/sand/grit to move around in the lines. Check the seal for grit, rub your finger along the inside where the seal is. Lift up the overflow tube and run finger along the bottom , better, get an old toothbrush , cut off most of the handle and "brush" the bottom of the seal, then turn the brush around and brush up on the part that closes down on the seal when you let the overflow tube go

Flapper not seating properly,either get new flapper or try a old trick i've used shut off water to tank and drain tank then add hot water to tank and let set for a while sometimes that will soften and seat flapper it's worth a try it's free.

When water goes over into overflow tube then that means 2 things.
The rubber flapper at tank bottom is good and does not need replacement at this point.
That leaves 2 possible problems.
1) The flush valve needs to be adjusted so water turns off sooner.
Flush valve lets water into the tank.
For example if you have a float ball on end of brass rod, just bend the brass rod so the float sits lower in the water.
If you have the 'fluidmaster' then a float rides up and down with water level. There is a metal rod with a metal clip. Squeeze the metal clip and move it downward on the metal rod.
2) If water will not turn off after adjusting flush valve, then replace flush valve.
Local hardware store sells the part and can help with instructions.
You need a crescent wrench or large adjustable pliers.
Plumber can also install the flush valve.

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the ball **** fill valve is a poorly designed valve. replace it with a fluidmaster fill valve and a fluidmaster flapper. flappers do go bad after a year or ten depending on your water quality and choice of flapper but the fluidmaster fill valve will last a long time also. you can also get the water saver fill valve by fluidmaster and there is also a conversion set to change your toilet to a dual flush. all this is at lowes and there is a plumbing pro there to explain further. feel free to give me a positive rating. thanks!

If you're talking about the fill tube sticking in the latched position (not dropping), it's probably due to a sticking flush cable. Call Fluidmaster and they'll sen a replacement part.

Buy a fluidmaster flush fixer complete kit. about 20.00 or so includes flush valve, flush flapper, tank bolts flush handle. Follow directions