Valve adjustment i have a kohler 1 piece elongated toilet (tank#3466) and the tank fills properly but the water level slowly drops until the auto-fill kicks on and refills it. is this an adjustment problem with the flush valve or fill valve or a bad flapper? any suggestions? thanks.

Keep in mind that if you limit the amount of water too much, the 3.5 gallon toilet will not flush properly.

This looks like an old Kohler Rialto toilet. The proper way to adjust the water level is to tighten down on the adjustment screw located on the very top of the fill valve. The fill valve is the the piece that the float ball screws into on the left side of the tank.
Tighten the screw down and flush the toilet. Wait for it to refill, and check the level. If you need less water, tighten again, let fill and check level.
There are also two old school methods to save water in your toilet. One is to put one or two bricks into your toilet tank. This reduces the amount of water that fills the tank. The second method is if the fill valve has a float ball on a metal rod, you can bend this rod down into the water. This makes the fill valve shut sooner. Don't bend too far or too fast because the chlorine in the water weakens the brass rod that the float ball attaches to.

Either the bottom outlet washer or the inlet valve washer needs replacing. It is a common condition, and if unsure, call a handyman in. An expensive plumber should not be needed.
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The problem is your flapper. It is leaking water into the bowl, causing the valve to kick in as the water level slowly drops in the tank. It will also solve most condensation issues as well.

Inside the tank, on a lever arm there should be a cylindrical float that rises and lowers with the water level. Attached to the float is a float rod with a clip that can slide up and down the rod. You can adjust the water level by sliding the clip down to reduce the amount of water entering the tank. As the water fills the tank, the float rises, pushing up the float rod, which in turn pushes up the level that controls the valve allowing water to enter the toilet.

Hi chanryan...
You need to adjust your float level in the tank.
Look on the arm of the float ball and there should be a screw that you can adjust the level of the tank water.
Turn the screw to raise the level of the water in the tank, to just about a 1/2 inch of the overflow pipe
If it will not adjust then you will have to replace the float valve (ballcock...is what it is called)
Please take time to rate me

the tube that goes from the fill valve to the fill tube may not be installed correctly. the water must be going in the tube and not the tank. also it is a water conserving toilet so it uses less water also it is a comfort height toilet and to make it taller the bowl is extended so the water may seem even more shallow.

Adjust the float attached to the fill valve. Some simply slide up and down on a racheted adjustment bar. Others screw up and down for adjustment. Flush after each adjustment until the proper fill level is acheived. Make sure there is still a sufficient amount of water at a given level to flush the toilet properly.

There is a volume control screw on the valves usually a plastic thumbscrew on side of valve turn clockwise until they quiet up the plumber should have adjusted that these are very tempermental toilets but when adjusted properly are excellent toilets I have 2 in my own home

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.

Make a small mark with a pencil or marker that can be erased of were your water line is in your bowl. Pour some water from a bucket into the bowl SLOWLY and see if the water line rises or drops back down to your original mark. If it drop back to the original mark, then that is the way the toilet was made. You won't be able to do anything about it. If it rises and stays at a higher level, then you have a problem with the fill tube in the tank. You will need to call a Pro!