Replacing Dishwasher Parts

Dishwasher Basics

Fixing a dishwasher is not a difficult task. But it does require good diagnosing skills and a simple understanding of how a dishwasher works. A dishwasher combines hot water with dish washing detergent and sprays it over the dishes, silverware, pots and pans. It pumps out the dirty water and then rinses the contents clean, using water and a rinsing agent. After expelling the rinse water, the dishes are dried either by heat or by forced air. Most dishwashers have selector dials which let you choose the time cycles for each of these functions. A water inlet valve lets the water flow in until a float signals that the machine is full and turns off the flow. This prevents the dishwasher from overfilling. That triggers the machine to release the detergent into the hot water mix. The heating element is critical here because if the water is not sufficiently hot the machine will not do a good job on your dishes and pots.

The dishwasher motor works a pump which turns spray arms that spray the hot water detergent mixture over the contents of the machine. The pump reverses from time to time to push the dirty water out the drain. When this is done, the rinse cycle begins and finally when all of the rinse water is pushed out down the drain, an electric heating element heats the interior of the dishwasher to dry the contents. Most dishwashers have a fan to circulate the hot air and a thermostat to prevent the machine from overheating. Some machines have soil sensors to measure the clarity of the water and when the water is sufficiently clear, the machine knows that the cycle is finished.

Diagnosing the Problem

Now that you know how a dishwasher works, you are ready to diagnose the problem. Based on the symptoms your dishwasher is exhibiting, you can arrive at a possible cause or causes. If your dishwasher does not work at all, the most likely culprit is a blown fuse or circuit breaker. This is the simplest of repairs. Just replace the fuse or flip the circuit breaker. If that doesn't work, then inspect the wiring to make sure there are no loose connections and tighten any one that is loose. The next possibility is the door latch switch. The machine will not work unless it senses that the loading door is properly closed. Clean or replace the switch if necessary. Next test the selector switch and the timer. If necessary, these are easy replacements. If there are still no results, test the starter relay for the motor and replace if necessary. Finally, if all else fails, your problem is with the motor and you will have to get a new motor and replace it.

Jammed Motor

If the motor works but you are getting no dish washing action, then you need to unjam the motor or the pump.  Check the drive belt and replace if necessary. If everything is working properly but the machine is not filling with water, then first check the water supply to make sure it is turned on. This will be a valve under the sink. Next check the door latch and the float assembly. If the latch is not working the machine will not draw water and if the float is improperly positioned the machine may sense that it is full even if there is no water inside. Check the water inlet valve and the drain valve to make sure they are working and replace if necessary.

Check Valves and Gaskets

If the water does not drain properly, check the drain hose to make sure there are no restrictions. Unjam the motor and pump and check the drain valve and drive belt. Finally check the timer motor. Replace any defective parts. If the dishwasher is leaking water then inspect all of the seals and door gaskets and make sure they are sound. Check the pump to make sure it is working properly. If detergent is leaking out, make sure that you are using the proper detergent and inspect the spray arms for possible damage. If water leaks back into the sink, inspect the air gap.

Drying Problems

If you are having drying problems, check the heating element, the drying fan, and the thermostat. And if your machine is too noisy, examine the motor mounts and look for any obstructions to the spray arms. And if you are having a problem with the door, check the latch, the springs and the hinges.

Incomplete Wash Cycle

If the cycle does not complete check the timer motor, the thermostat and the heating element and replace as necessary. If the detergent cup is not opening examine the timer motor, the actuator arm, and the bimetal assembly.  The timer motor, heating element, and thermostat can be responsible if the cycles are too long.

It is a good idea to keep the walls of your machine well scrubbed to prevent rust. If you follow the steps listed here you can maintain your machine in good working order.