Working on a Whirlpool washer top load. Customer said we are the third tech here on washer. He says that washer won't drain all the water.Ran a drain spin cycle and rinse drain. After diagnosis it was an installation problem to drain pipe. Which leads to restriction in the drain line. With this Installation its impossible to continue a thorough diagnosis with unit improperly installed. Told customer get installation done correctly on unit and he would most likely notice the improvement