Toilet flushes normally but then fills very slowly. Tank refills completely but the fill valve turns back on every 10 minutes or so for 15-20 seconds. There are no external leaks so it appears a small amount of water is getting past the seal on the flush mechanism.

Remove and clean the flush valve and the flush valve seat(it is the flap that opens up to allow water to flush the toilet). Once the edges of the valve and the seat are cleaned, possibly with "0000" grit bulldog steel wool, it should not leak anymore. To make sure it is not leaking, once tank has refilled completely, put some food die in the tank. If, after 10-15 minutes, the water in the toilet bowl is colored, you have a leak from the flush valve. Replacing the flush valve is very easy - just bring the old one with you to the hardware/plumbing store and ask for a replacement. Blessings and good luck!!

It's hard to answer such a general question. I will assume your reference refers to a toilet, and that 'pulse' is regards a recurrent slight refill action of the tank fill valve. If this is the case the cause is probably a slowly leaking flush valve. When the tank water level drops enough to activate the fill valve, there will be a slight refill action (pulse) to top up the tank water level. It will repeat until the leaking flush valve is fixed.

My sister has a two year old Jacuzzi toilet that worked fine until a few months ago. Then it started to take 10 minutes to shut off after each flush. I lifted the tank cover and immediately saw the problem; at least 90% of the refill water was going into the refill pipe instead of the tank. Upon examination I discovered that the plastic part that holds the flexible refill tube to the vertical refill pipe was broken. This part not only holds the refill tube in place, it also has a small orifice at the end to restrict the flow into the pipe. The part was broken in such a way as to let nearly all the water go into the refill pipe instead of the tank, hence it would run for 10 minutes after the toilet bowl was full and waste all that water. I found a small coarse thread stainless steel screw that fit into the plastic attachment piece to help plug the orifice and cut down the amount of water going to the refill pipe. Now the toilet flushes and refills in less than 2 minutes. I'm in the process of trying to find a replacement for that part but so far no luck.

Hi!please kindly check your fill valve if it is working correctly.I thought the problem is in your fill valve.Kindly adjust the floater of your fill valve.

Several ideas. Start to fill? Have you looked inside the tank to see what's going on? If it just filling very slowly, then you most likely have some calcuim build up inside your flush valve blocking some flow, if this is the case you will have to clean the flush valve. If your flush valve is staying up and the toilet is "running" unitil the float drops. The float (either the arm ballcock style, or newer fluidmaster) is rubbing on either the flush lever or side of the tank, and taking longer to drop to let the water start flowing. I

More then likely the power valve in your flush master ball valve is out.. Replace flush valve and should fix problem. Home depot sell fluid master for like 7.50

Most likely, you do not have a good seal on the flapper valve at the bottom of the tank. To confirm, try this:
Turn off water and flush toilet. Then lift up the flapper valve and put a light coating of vaseline on the mating surface where it contacts the toilet tank when closed.
Turn water back on and see if it continues misbehaving. If that fixes it, it was a bad seal. Usually that is all it takes.

Lift the tank lid off, place it somewhere safe for a moment, and look at what happens: If you're talking about jiggling the handle to get the tank to start to fill with water, then it sounds like the chain or rope is out of adjustment. It can't be TOO TIGHT or the water will leak past your flapper (will cause your dripping noise, tank water level will leak down, causing constant refills), and it cant be TOO LOOSE or the toilet won't flush correctly. Since you didn't mention trouble flushing the toilet, I think that it may be a little too TIGHT. When you jiggle the flush lever-it is supposed to pull a chain or cable to open the flapper at the bottom of the tank. Flush the tank and watch what happens-all the way through to refilling the tank with water and shutting off the water refill valve-Does the flapper get stuck on the chain or something? It is supposed to fall back down to allow the tank to refill after flushing out your toilet. Does the chain look very loose? The dripping sound you described indicates that the flapper is not sealing 100%. The flapper is very easy to replace, you just have to get the adjustment set for when you flush the toilet how sensitive you need it. You amy have to play with it a little bit before you get the adjustment correct.

Hope this helps!

It sound like you have debris caught in the fill valve. Remove the top where the washer is and put your hand over it and slowly turn the water on to flush the fill valve. Replace the washer with a new one and then replace the top.

If you have the old ball and **** style, replaceing the diaphram is harder so I would recommend replacing it with a fluidmaster fill valve. Hope this helps.

You need to replace the flapper and you will need to purchase one specifically for the Kohler toilet. I have the same toilet and tried using a generic flapper and from experiance, it didn't work until I bought the correct one and I'm a plumber! Have a great night.