Paul B Elizabeth , CO September 14, 2015 Appliance: Maytag Dishwasher MDB4100AWW Maytag Dishwasher Mdb4100aww: No error codes just not washing like it was supposed to and not cleaning dishes. How to replace O-Ring. Ordered the new o-rings for the pump housing and main filter screen unit. Cleaned all water hardness and other debris out of all parts. Main filter and inside parts clogged with water hardness/limescale and other debris. The 3" wide round filter internal was completely clogged with debris and some of the filter holes we crystallized with water limescale. The pump was in good shape but all the filters and parts just needed to be cleaned. Some useful tips on this Magtag Jet Clean (MDB4100AWW) washer: To replace the pump gasket, take the 2 bottom lower covers off and underneath the tub where the motor is located there is a lever on the bottom left of the dishwasher next to the motor that can be depressed and rotated clockwise (away from you) to release the main unit from the tub. This will give the necessary space to properly replace the pump gasket. Then once you have the gasket properly installed around the base unit make sure that the arrow on the inside of the tub aligns with the screw post. This is for the alignment of the hoses underneath. Now you can reach underneath and slowly using the lever, rotate it back counter clockwise (towards you) to set the main unit back against the pump gasket while you pull the lever towards you. There are several notches where the lever will sit once you get it snug. Be careful not to over do it! Now you can assemble everything in the order shown in the diagram layout. Also be sure to put the main nylon washers in the correct spot when you re-assemble things. On the diagram, it shows them together and that's because both of them go on top of the internal rinse arm in the center. I couldn't remember where they went because I had some time between ordering parts and putting things back together and did not document where they cam out. I found a video on YouTube that illustrated replacing the pump housing gasket and that helped me figure it out also. Once I started the dishwasher with a minimal load, I checked for leaks underneath and there were none! The dishwasher, even though 15 year old, ran like a top and was much quieter. 9 People found this story helpful Do-It-Yourself Rating: Repair Time Estimate: 30-60 minutes