First off, I must give thanks to Partselect.com for excellent service. They had the parts I needed, a Diagram of how the parts should go into the Dishwasher, and shipping was very quick and reasonable priced. Thank you Partselect.com.
After dinner we heard our Maytag MDB5100AWW dishwasher start grinding during its wash cycle. Needless to say we found this quite concerning, as this is not what a healthy dishwasher should sound like. After fiddling around with it, I started researching the issue and found Partselect.com where it was stated the “Discharge Housing Assembly (Discharge Pump Housing)” was a common failure point. After disassembling the “Pump and Motor” section of the dishwasher, it was confirmed that the Discharge Housing was indeed broken. Since this Dishwasher is over 8 years old, I figured that I might as well replace a few other parts as well, since I'm in there working on it.
Following the blow-up image of the Pump and Motor picture;
Unscrew part 34
Pull out part 1
Lift Part 2, which is attached to part 36
Unscrew part 5 (6 of them) from part 4, be careful not to loose part 3, sitting inside part 4
Lift out part 6 and 7
Unscrew part 8 and lift out part 9
Unscrew part 27 (three of them) and lift out part 11
The bottom plate of this part is the broken part.
Now, since we are in here replacing a part, we might as well replace a few other parts and give this dishwasher a little longer life. I opted to replace the following parts as well, being that my dishwasher was over 8 years old and the gaskets were showing some age.
Part 4 – Pump Cover and Secondary Filter Assembly; I replaced this part because food often gets caught inside the filters and will throw off the balance during a wash or rinse, thus putting premature wear on bearings and o-rings. My filter had a bunch of food on one side, and the only way to remove the food was to slit open a section of the filter, thus damaging the filter screen.
Part 37 – O-Ring that goes inside the Pump Cover and Secondary Filter Assembly. O-rings are rubber and do wear with age. My dishwasher didn't even have this o-ring; now it does.
Part 3 – Lower Spray Arm Seal; I noticed when pulling these parts out that the hard water in our living area was making these somewhat brittle. When ordering these, get two of them, as the picture indicates. If you order one, the package only contains one, and not two was the image shows it should have.
Part 11 – Discharge Housing Assembly (Discharge Pump Housing). This is the part that is making all the grinding noise. The new part will show that it is built a little differently. It appears that Maytag figured out the weak design of this part and made the replacements stronger.
Part 17 – Even though I ordered this, you don't need to order this part if you order the Part 10 kit. The part 10 kit will include this o-ring. Because its an O-ring, I replaced it; as stated above, o-rings do breakdown.
Part 25 – Pump Gasket; This part should really be called the Pump Housing Gasket, as it isolates the Pump Housing bucket and the Dishwasher tub. I bought this because my original gasket was looking pretty nasty and was coming apart.
Part 10 – Seal Kit (Motor/Pump) (Motor/Pump Impeller and Seal Assembly), this kit includes several components that if purchased separately would easily be twice the cost of this kit. Again, seals and Motor Pump seals are a good thing to replace when needing to do work inside the dishwasher.
Continuing on from the previous dis-assembly list;
Unscrew part 12 and remove part 14, 15 and 16.
Unroll part 17 (o-ring) and remove part 18.
Unscrew parts 19 and carefully remove part 20, being VERY careful to not loose part 39.
Lift out part 22, which will include the bearing inside of part 22.
Pry out part 24 with a pick (the replacement is in the kit of part 10).
To remove part 25, you must Remove part 12 of the Door Assembly (see the Door image) to reach the motor element.
Next unscrew part 14 of the “TUB” i
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