That gray rubber disk should just lift out and I'd try that first. If not, then it's probably that missing piece of plastic in the rim (near the 6). But it looks like that is all one piece and part of the entire dispenser, which would make it more difficult to replace.

Are you positive there is a leak, from that point?
In the past, how long could you go before having to refill it, and how long is it taking now?
There's also the possibility the level adjustment mechanism (1-6) is no longer working properly. Even though you have it set to 1, it may be dispensing what would be 5 or 6.

The gasket looks to be in good condition, is it still pliable?

The dispenser can't really leak from there anyway especially when the door is closed. Anythings possible but this is not a strong avenue to pursue. I've seen one or two of these dispensers go bad but it's always a failure inside the door panel at the reservoir . It makes a pretty good mess in there. I'd suspect the pump/dosage meter is malfunctioning and dispensing too much liquid.

Where did you notice your leak? Or are you just assuming there is one b/o the increased usage?

antss & fauguy: Many thanks for the help & advice. I am positive it is leaking from around the seal of the fill port. I can see the streak of fluid running down the inside of the DW door. What I tried tonight is to wipe up every spot of rinse aid from the door and all around the fill port, in the bowl recess of the port, and the seal. Then I closed the dispenser flap, and raised the DW door to the closed position. After several minutes there is a streak of rinse aid all down the inside of the DW door & if I open the dispenser flap you can see the trail of rinse aid where it dripped down from the fill port and channeled down past the orange latch and onto the inside of the DW door.

antss: Yes, I do take your point, and the seal is pliable and appears to be in good condition. I am only hopeful because I see the leak is definitely coming from under the seal and also the trail does not seem to go too close to the gouged area of the fill port which I am hoping is a good sign.

I called Miele this afternoon. Tech support was very negative & said whatever, the whole dispenser would have to be replaced & thought the replacement seal was not available. Service call would be $175 + another $170 for the dispenser itself, all + tax I presume. However, when I spoke to parts I got a VERY helpful & knowledgeable gal named Wendy and she was just great (she said she used to work in tech support). She listened to my report and she was very positive about first trying the seal. They have the seal in stock & after a bit of discussion she kindly agreed to ship me a complimentary one to see if it fixes the problem, which is great. I think she may have either taken pity on me or been impressed with my determination to isolate the cause - not sure which. It also helped that I already order my supplies from them so I was in the system.

I will post the results of the seal replacement.

Tina

I do not have the Miele but but have a question regarding the pics and what you wrote above in your troubleshooting.

In the pic, I can see the grey gasket in the cover. If you look at the photo in the 3 o-clock position, in the round cover, it appears that there is a notch there. This would be directly above the orange latch when the cover is cosed. Don't know though if that hole/notch is supposed to be there or if something broke off the cover, like one of those grey tabs that appear to hold the gasket in place.

todds, I see the 'notch' you are talking about in the round gray gasket at the 3 o'clock position, but when close that would line-up to the number 4 on the plastic dial, not where the orange latch is.

Gosh, thank you for all the help and the detailed observations. I checked out that notch: It is definitely original and meant to be there. The notch carries on underneath the gasket. My new gasket is supposed to arrive on Tuesday. After that I will try it out and report whether or not it fixes the problem. If not then I may have to resort to replacing the dispenser at some point.....

is the leaking happening every time you open the door or only when you run a wash cycle?

does it leak (in same place)if the dispenser door remains open as opposed to closed?

is it possible you over filled it?

antss: Those are very good questions. I have definitely not overfilled it: It has been leaking even when the dispenser was filled several days earlier and plenty had been used already.

Here is what I saw today: I came home and a load had been running. It was finished and everything was dry. I opened the DW door and there was NO sign of a leak: the door was perfectly clean. So it seems that after that load was finished it did not leak. I opened the dispenser flap, closed it again, closed the DW door and within a couple of minutes the leak appeared: rinse aid dripping down the door, right in line with the center of the fill port. I wiped everything clean and this time I closed the DW door with the dispenser flap OPEN, as you suggested. The leak was MUCH stronger now - and it is exactly as it is with the flap closed, in the same place and the same pattern. So I conclude that the leak with the flap closed looks just like rinse aid is dripping out of the fill port.

I am wondering if the heat of the wash cycle caused the seal to set better resulting in no apparent leak at the end of the cycle? However, once I break the seal by opening the dispenser flap the leak shows up again.

This is mysterious! I hope the new seal arrives tomorrow so I can test this out.

Thank you for all your help!

I think what you mentioned above is good news. It seems to point to an issue with the gasket.

OK, here's what I think is going on: your dispenser is broken internally.

Like I said before - it's nearly impossible for rinse aid to comeback out of the reservoir and fill the fill cup and then leak past the gasket. It's a one way trip when filling the cup.

Now - when working correctly, the door is opened and a metered amount of rinse aid(determined by that rotating tab) is let into another chamber through a solenoid controlled door. It's just behind those 3 slots you see. The solenoid doesn't allow RA to flow unless called for in program.

I'm sure you've figured it out now, the solenoid is broken in the open position and allows RA into the dispensing chamber EVERY time you open the door. When you close it it runs out of the slots and down the door, not out of the gasketed circle.

So, you do have a leak - sort of. You''ll have to replace the whole combo dispenser unit and I think they are around $150, but don't hold me to it. Pretty simple to replace by removing your cabinet panel, unscrew the front door skin and then un-do half a dozen screws retaining the unit.

antss: Many thanks for your analysis. You are no doubt right - it is especially telling then that after a cycle there was no leak, yet a leak that is permanent appears after I open the dispenser door. I am not following something though: I understand there is a solenoid that is activated and opens to allow the determined amount of rinse aid out at the appropriate point. As I understood from Miele at that point the rinse aid is washed into the main chamber through those slots. But you seem to be saying that the actual main dispenser door is opened at some point too - is that right, or am I being dumb? I guess I am not sure what you mean about RA going into the dispensing chamber every time I open the door - do you mean the door of the dispenser or the main DW door..

Sorry, not meaning to be obtuse, but I guess I need a step by step explanation of how the dispenser works during and between cycles...

Thanks too for the replacement instructions - I know I probably COULD do it but I am leaning towards avoiding the aggravation. You are right about the price - I was quoted $168 for the dispenser. The service call with a Miele tech would be a fixed charge of $175 which doesn't seem TOO bad. If I do get it replaced I think I would use a Miele tech rather than local service because local service may well not know much about this machine and could easily run up a bill that big in an hour or two....

I am going to run a load now and see if it is not leaking again after the load is finished. This time I will NOT open the dispenser door and I will see if the leak reappears before the next load...

not obtuse - it's tough to get your head arount since you can't see any of the workings. The door you see and use to fill the dispenser doesn't open during a wash - only when you fill it.

the "door" I'm refering to is hidden inside the dispenser - you cant see it unless you remove the unit and then dismantle it. It's allowing RA to pass from the internal reservoir into the DW tub at the correct time - if it's working.

Most likely yours is stuck open and is allowing RA to flow EVERY time you open and close the DW door. There is no fixing this through normal channels. Solution is to replace the entire assembly.

Just wondering, but how old is this dishwasher?
If it's getting old(er) 8+ years, then maybe instead of spending almost $350 for parts & labor, get a newer up-to-date model?

Thank you antss for all your patience. I think I see what you are saying now.....are you saying that the action of opening the DW door and then raising it to the closed position again would basically mechanically shake RA out of the dispenser, via the presumably broken & continuously open internal dispenser door? That would make sense as to why I had a load where afterwards there was no leak until I opened and closed the DW door. The latest load was different: at the end of the load I could clearly see the leak still. I will say though the leak does appear to come from the very center of the dispenser and not under the grill slots.

I think you are right that the dispenser is broken....it is going to be an expensive repair: essentially $400 with parts, labor & tax. The DW is 6 years old and I thought these units should go forever... do you think it is worth spending that much on it, I mean this machine surely should not be dying at this point. What's the alternative to using the dispenser? I wonder if I can manage without rinse aid...or perhaps that is stupid. I use the Miele tabs. Thank you!!

RE: repair versus new - repair unless you have lots o/$$$ and time to sell the old unit for kicks.

RE: these lasting forever - they have a longer lifespan than most, if not all. That doesn't mean that all units are trouble free and will run 20 years with out the need for service. I have a client near me with two of your model's older brothers. One has needed a new selector switch and a filter screen that they broke. The other has been perfect in 10 years.

RE: 400 bucks. Sound a bit high to me- not egregious but a bit high. Closer to $300 would be what I look for. Tax on part only, not labor.

antss: Thanks again for your advice. I agree the repair cost sounds high. I think if I needed the dispenser I would follow your useful instructions & try to install myself....

I don't know whether I should post this or not....but...by some miracle the new seal has indeed fixed my rinse aid leak. I received it yesterday. I cleaned the inside of the DW door carefully, changed out the seal, raised the door, waited a few minutes and...no leak!! I waited overnight and no leak!! I have since run a load, no leak, and opened the dispenser door several times since and no leak. Yeah!! On inspection the old seal looked rather concave, viewed from the top as you have the dispenser door open. I wonder if it had become somewhat lax or something. Or even if my change to the Finish rinse aid destroyed it? I had been using Jet Dry forever, or Miele. Recently I changed to a bottle of Finish...Now I am back on Miele RA and I don't intend to test out the Finish again. I intend to call Miele to tell Wendy in parts who was very helpful that the seal fixed it. I think she will be pleased too.

Thank you everyone, especially antss, for your patience and help in diagnosing this problem. I must say I am very relieved that I seem to be OK for now. This DW is the hands down best appliance I have ever owned - the results and reliability have been stunning since day 1. I always have regretted not getting the Miele washer back in the day when the Euro 240 V machines were available. I got the Bosch Axxis instead. It's OK, but I've already had major repair (ie the motor replaced). Next time it will be a Miele, but I'm hoping when the time comes I can get the small Euro 240V machine.

I'm very surprised this worked? I can remove my seal and not get a leak to occur like you describe.

Glad it worked out for you.

Hi Tina, so glad to read that your Miele problem is fixed! Thank you for sharing with us -- for both this and the Blue Star lessons learned -- you are my appliance heroine!

antss - maybe I am hoping too soon then. I was fully convinced by your reasoning and I do see that the RA should not come back out of the dispenser once it is filled. I'll try removing my seal and see. Perhaps the problem really is what you say and it will reappear. Perhaps something is wrong with my dispenser then if the RA should not come back out of the fill port as mine seems to be doing. Maybe there is some check valve inside that has failed. If it reappears any time soon then a new dispenser it is. Thanks again.

antss: Yes, I do see RA coming out after the seal is removed - leaks like crazy! If yours does not then clearly mine is broken as you say. I am supposing then the fill port valve is kaput. I was hoping too soon.... Thanks.

tina - don't panic just yet, I got curious and called one of my engineer contacts and I am almost certainly wrong in this instance. I was thinking of the ancient units of over a decade ago.

It is possible for RA to come back out of the fill hole on your unit, so the gasket is not just a secondary precaution like I first thought!

Fit the new gasket and simply monitor the RA usage, if there are no leaks on the door AND your usage seems normal 30-50 loads per fill depending on the setting then there is not a problem with the solenoid.

Sorry for the agnst.

antss - THANK YOU SO MUCH for all the follow up on this - way beyond the call of duty. I called Miele before I saw your post and they said the RA should not come out either!!! I reckon they were thinking of older units too then! I am glad to hear that mine appears to be OK! I have it on the lowest setting. I will fill it to the top and log the number of loads I get. Thanks again! My dishwasher lives to fight another day!!

"I reckon they were thinking of older units too then! "

doubtful - I'm pretty certain anyone answering the phones was not with the company way back then + it's still not exactly how I remembered the design.

anyway - hope yours is the simple and free fix.

Fine fellow, that antss.

I filled my rinse aid earlier this week and have it on a setting of 1. Last night I removed the rubber insert seal on the rinse aid door, closed the rinse aid door, and then closed the dishwasher. Waited 30 seconds and opened the dishwasher back up. I could see the rinse raid running down the door about 7". I then opened up the rinse aid compartment and it was in there too some. I wiped it out and put the gasket seal back in place....tried it again and got no leaks.
This is on a 5 month old Diamante.

That is exactly what antss is saying: rinse can back up out of the newer models. It is strange because my gasket didn't look all that bad: I have my suspicions that it may have been weakened during the recent phase that I used Finish DW tablets: they have a chlorine like smell, or even the Finish rinse aid. Not sure though how the main detergent could get to the seal. In any case I am now back on Miele tabs & RA and that's where I am going to stay!

Thanks antss! Seems that Miele did not know that the gasket could go bad like that. I am glad this is posted in case anyone else gets the problem.

"Seems that Miele did not know that the gasket could go bad like that."

It's possible that yours is the first documented case, I'd never heard or seen this problem in 15 + yrs. It threw me for a loop, though Miele sure sees a lot more cases than I do , but still possible that this is the first.