Slide the upper rack outwards and hold it the upper rack stationary while pushing back on the middle spray arm … Step by step instructions on how to replace a Lower Spray Arm for Frigidaire FDB4315LFB3 Not cleaning dishes properly #AP4453743 for Dishwasher made by Frigidaire, Kenmore. Use an object such as a toothpick or other tool to open up the water jets on the dishwasher spray … The spray arms can accumulate hard water in the jets. This causes water to not spray out with force therefore not cleaning your dishes. Step 2: Remove the Spray Arm. If your dishwasher has a spray tower or spray cap attached to the top of the arm, you must twist it off or unsnap it to access the nut. Spray Arm Nozzle Blocked/Clogged. Remove the spray arm if it is faulty or you have not identified a problem. Before you begin, switch off the power to the dishwasher. Be sure to clean the spray arms to remove the hard water that has built up. The upper spray arm is part number 154754502 and is available to order at Sears Parts Direct . The middle spray arm can be easily removed for cleaning. Rinse it with a high pressure spray … Clean the piece by soaking it in warm, soapy water to get rid of grime. Note: This video is …