Waterlogged tank

I have a vertical tank that is waterlogged. There is no air baffle it it, I just let air out manually from the top when there is air in the lines.It is a goofy set up but it works (last 10 years) I replaced the schrader valve but it didnt help. I have shut off the breaker and let water out 2x till 1/2 empty. But it still gets waterlogged. Is the check valve (where schrader valve goes into) bad? I replaced it once but cant remember why. Thanks for your help!

I am not really sure what kind of tank your dealing with. Most tanks have bladders inside them. A steel tank with a rubber bladder that holds air inside the tank . If its a bladder tank that you have, with the pump shut off and the water valves to the tank open and no water pressure or water is running out of the tank, the pressure at the schrader valve should be about 2 pounds less then your( on pressure) of your pump. In my case my water system my pump is set to come on at 30 lbs and off at 50 lbs pressure, so my tank pressure is set at 28lbs.
The check valve is usually on the suction side of the pump. It keeps water from falling back into the well. I have never seen any schrader valve used around a check valve.

Larry

The Schrader valve on the check valve is how air gets in, not out. The Air Volume Control or AVC is how the excess air gets out. There should be a fitting about half way up the side of the tank. It has 1 1/2" threads into the tank, and sometimes has the pressure gauge screwed into it. AVC's and the rest of the air charge system parts usually don't last very long, which is one reason bladder tanks have become popular. Install a new AVC and you will be good for about 6 months to a year.

Go to the link below for a really good diagram of how the pump system works. Scroll down to "Piping Configuration" at the bottom of the page. Sounds like you have an "air charging system" with a bad schrader valve. This schrader valve is not like the one in your inner tube, it has a vacuum relief feature that lets it open to allow air to enter the pipe after the pump shuts off. You can get the right valve from your plumbing supply house. They clog easily, so I change mine a couple times a year.
hth, Ichabod
http://www.pumpsonline.com/installationinstructions.htm#PRECHARGED DIAPHRAGM TANKS

Zip tie a stainless steel brillo pad around your schrader valves and they will keep out bugs and last forever.

Many in line auto fuel filters slip right over the stem too.

Plumb the schrader with tubing or hose so there is a few feet of upside down inlet.