I bought a used stf 15 bunn coffee maker , i hooked it up to the water line , and plugged it in , my problem is that it will run about enough water for about 2 pots , i hear it click when the first pot gets full but it keeps running also when it starts to fill water runs out the top of it around the sides where the top cover screws down , is this maybe fron to much water pressure ?

Yes that is possible. There is a pressure regulator that is normally mounted on the back of the coffee maker. On older models the filter and pressure regulator may be inside the cabinet accessable by removing the bottom panel of the coffeemaker. The pressure regulator is a hexagon shaped usually brass fitting about 3 inches in length. The filter looks much the same. Both of these brass fittings should be somewhere in the water line between the wall faucet and the water inlet of the coffee maker. If not there the unit will overflow if you water pressure is over 40 psi in your location. These fittings are available from restaurant equipment stores and on Ebay for example. There is one other thing you may try. If you take off the panel directly behind the coffee pot you will see two adjustments. One is a temperature adjustment and looks like a small pin sticking up with a smaller pin at 90 degrees from it. The other adjustment is a timer. There will be a dial on the timer. This timer sets the amount of water per cycle by controlling the time that the fill valve stays open. Turn the timer counterclockwise by about 25% and hit the brew button again. If it overflows reduce the timer again. If you don't have a pressure regulator, you may not be able to turn the timer low enough to prevent the overflow situation. Good luck!