Piston and Nut Assembly

Removed 4 screws, took off basket covering, put new part in one turn, then replaced covering. Plumber had come out, I watched what he did, he had to order part and come back. I asked how much he didn't know but said cheaper than buying a new dishwasher. When he left I started calling around about the little plastic part that I needed. Part was $15.50. They called and said it would be $110.00. Needless to say I called them out and ordered the part myself and put it in. Took me like 6 minutes and cost $21.69. I was so mad about this situation that I even got my service call money back that I had already paid.

FILTER GASKET ASM:

1. Manually unscrewed the lower dishwasher sprayer from the base of the dishwasher. (The filter gasket cannot come out with this in the way.)

2. Using a nut driver, unscrewed the old plastic filter cage in the rear.

3. Thanks to a tip from another user on this site, I carefully pried up the metal grommets on the two plastic studs in the front. I did this slowly with a flathead screwdriver, as I was worried about breaking the plastic. (Some plastic did whittle off of the studs from the sharpness of the grommets, but not so much that they were ruined.) Note, the studs look like something that can be replaced if you break them. They are not molded into the tub, as far as I can tell.

4. Removed the old (rotten looking gasket). Be careful! The edges around the filter drain are sharp. Used a turkey baster to suck out water from the filter area and wiped away mildew. The filter recess had broken glass in it and some other yucky stuff.

5. Easily reversed process with the new gasket. The new one has a lighter color and has the plastic, upside down basket thingy built-in. (No sharp edges). I pushed the metal grommets back onto the plastic studs, working them down as tightly as possible. They seem to be holding well.

Piston and Nut Assembly for Check Valve:

I wasn't sure I needed this, but ordered it anyway after seeing comments that the seal can corrode.
Mine looked ok, apart from food build-up, but I replaced it anyways.

1. Removed the screened housing that covers the length of the bottom-rear using nut driver.

2. Unscrewed the existing valve manually. It was easy to do. Cleaned area out as best as I could.

3. Reversed process with the new part.

TURNED OFF ELECTICAL AND WATER - TOOK FILLTER SCREEN OUT OF INSIDE, UNSCREWED CAP TOOK OUT VALVE AND REPLACED IT

After reading about this problem on an appliance repair forum, I learned that it is usually caused by a faulty piston valve. The valve is located under the rear screen filter and can be removed with your fingers. The parts arrived very quickly and we saved $$$ by not having to pay for a service tech visit and "mark-up" on the replacement parts.

Went to repair parts on troubleshooting and found check valve assembly to be most common problem. Went to parts diagram to locate assembly and found it somewhat confusing as to exact location. Ordered part(s) on percentage as the problem. Received part next day (great)! Pulled dishwasher out and found I did NOT need to do so to replace check valve which is replaced without having to remove dishwasher. The gasket replacement was not necessary as it seals sump area from bottom of dishwasher and not the valve as it appears on the parts diagram. It took about 2 minutes to replace valve itself and it was the cause of the problem.

Removed screws on the drain pump filter screens at the back of the dishwasher, unscrewed the check valve, screwed in the replacement unit, and re-affixed the filter screens.

I lived with the drain problem for 6 months and reviewed on line trouble shooting which all pointed me to a pump or solenoid valve problem. I pulled the unit and disassembled everything before noticing that the rubber washer/stopper at the top of the check valve had erroded away and was not preventing water from pumping back into the cabinet when the drain pump kicked on. Always check the condition of this check valve first if you dishwasher is not draining properly. It was so easy once I found the bad part.

Open door, remove lower wash rack, remove 4 screws holding screen in rear of inside tub with 1/4 inch socket. Unscrew piston and nut assy for checkvalve, sounds like a mouthful but it is only 1 part. Checkvalve has 2 small ears on it which allow you to twist it out, it has treads on it. Flapper on check valve flapper rots away and water pumps back into tub instead of being routed to drain line to garbage disposal. Part with shipping was just over $20.

First, I drained the water from inside the washer and removed it from under the sink. I wasn't sure if I had a clog in the drain line, so I dissasembled the drain under the sink and cleaned that as well. While cleaning under the sink my wife found her $4000 dollar ruby that fell out of her mothers ring a couple weeks earlier. It must have dripped out of the trap while I had water draining everywhere. Put drain back together and moved on to the dishwasher repair. Parts were easy to install after laying the dishwasher down on its front to access the bottom back side. Hooked everything back up and slid it back under the countertop and away it went. Had one small leak after running (water in line wasn't tight enough). A twist with a pair of pliers and that was resolved.
Fast shipping by the way! I paid a little more for the exit washer than I wanted to, but with shipping only from one source and delivery of parts at the same time made downtime as little as possible. I'm sure I saved $100 dollars or so by using this website for parts and tech info. And recovered a precious stone to boot.

removed screen at back of dishwasher from the inside. Twisted piston & nut assembly out by hand and replaced with new one. Very, very simple. Dishwasher works perfectly now.

took out 4 screws pulled piston out and changed put back together. very easy and inexpensive!! thanks

After two repair people were unable to solve the problem, I read similar stories in your forum and decided to replace the check value as a last ditch effort. Looking at your diagrams it seemed like an easy repair. Removed four screws with nutdriver and replaced value by hand. Ran washer three times and water drained completely. Still puzzled that this wasn't the first thing a repair person would check.
Websight very helpful.

Removed the 4 screws holding the filter screen assembly in the back of the tub. This exposed the Piston and Nut assembly which unscrewed fairly easily.
Replaced with the new part, put the filter screen assembly back in place ran the machine. The machine still stops with the blocked arm message - just not as frequently. The web researched fix with the piston and nut assembly replacement was obviously not the final answer. I am now out of options I believe except to bite the bullet and get a new machine. Any other suggestions are welcomed.

Remove shield in rear. Unscrew valve using hand. Screw new valve in place.

Remove the back filter to access check valve assembly. Twist check valve assembly to remove, not significant deterioration of rubber cap. Install new assembly. Re-install filter. Super-easy and effective!

Removed screen bottom rear andfound a plunger type part, unscrewed plunger and found it was distressed around it and did not close of a tight seal. Placed new part into location and dishwasher now proforms perfect...