Dishwasher makes a lot of mechanical noise when running
If your dishwasher seems noisy, check these:
An aging water-inlet valve can sometimes fail slowly, rather than all at once. It can shudder on and off rapidly, causing the incoming water lines to shake, rumble, and rattle--sometimes violently. If yours is doing this, replace the inlet valve.
If it's the motor that's noisy, either of these may be the "culprit:"
As motor bearings wear out, they can become quite loud when the motor runs. They wear out quickly if they frequently get wet, because the water washes away the motor bearing grease. Bearings can get wet if the spin seal is defective. Then there will also be water leaking onto the floor beneath the dishwasher. Replace the seal if it leaks (read about the main tub seal in the "It leaks" section, later).
If, from beneath the dishwasher, you can see a round, plastic disc that's mounted to the top of the motor (a "slinger"), it may have broken free of the motor shaft. If so, it could be rattling around the shaft while the motor is running. If that's the problem, you need to replace the motor.
If the heater fan bearings are rusted or worn, they may squeal, or scrape loudly during the drying cycle. If this is the problem, replace the fan motor. Alternatively, the fan blade may be loose. If so, you need to replace it.
Small fruit pits, toothpicks, and fragments of glass sometimes get stuck in the pump. When this happens, open the pump and remove the debris. The pump is usually mounted directly to the motor, then attached to the bottom of the dishwasher.
To get to the pump, you usually need to remove the lower rack, the spray arms, and the spray arm support from the inside of your dishwasher. A dishwasher pump isn't obvious. Look for an impeller--a round, plastic fan blade-type device that spins around and pushes the water toward the drain. When you can see the drain impeller, you should be able to see the clogging debris.
1 Look at the heater fan to check for rusty or squeaky parts. If defective parts are found, replace the fan. If not, go on to the next step.
2 Replace the water inlet valve, which is located at the bottom of one of the sides of the dishwasher, beneath the lower access panel. As a water inlet valve ages, it can sometimes slowly stop working correctly, switching between "on" and "off" every few seconds. This can cause a shaking and rattling noise. If this does not fix the noise, go on to the next step.
3 Remove the lower rack and the lower spray arm from the dishwasher, removing any screws as needed to do so.
4 Beneath the lower spray arm is a pump that contains a propeller. Check the pump for debris (like small bones, seeds, or fragments of glass) that might be causing the noise. If this does not fix the noise, go on to the next step.
5 Beneath the pump is the dishwasher's motor. Check to see if the plastic dish at the top of the motor has broken off. If it has, it may be rattling when the motor is on and causing the noise. In this case, replace the entire motor.
6 Check the bearings on the motor. If they are worn out, replace them.
7 If you cannot trace the noise to its source, try replacing the motor.
Sep 03, 2010 |