Zelmer Maestro 13Z012 Coffee Machine - Persistent Leak from Heating Block Post Gasket Replacement

Question

Express as in the subject. The butt gasket was damaged, I replaced it, but the problem has not disappeared, namely the steam escapes from the heating block, but from the very bottom, where there is an outlet under the buttstock and the steam flies inside the machine. Is there any gasket that can...

MARCIN.SLASK · Answer

Boiler leak:
- leakage through the gasket between the halves,
- leakage between the flask and the gasket - loose bolts securing the boiler to the sheet,
- lower half of the boiler is broken (near the fastening screws),
- leakage at the hoses (hose O-rings).

nioop · Answer

Probably a gasket .. I have never had a block crack ..

The manufacturer provides for the replacement of the entire thermoblock, so in the diagram you will only see the complete thermoblock.
Of course, you won't see the leakage spot on the diagram either.

There are two gaskets .. One simple O-ring can be easily purchased .. The second longitudinal .. O-ring only long .. Rather, you can buy only in specialized stores.

Tommy82 · Answer

I know a terrible crap because I had it.
For me it was the same, but in my case the "socket" of the buttstock was damaged, some erosion or other corrosion or a different stick. And the gasket practically had no chance to seal.
I had to disassemble it, as I remember it took a long screwdriver and then I sanded the iron wet on glass on fine paper. You cannot remove too much material there.

Where the seal 8 comes.
Before I got to what is damaged, I replaced two gaskets which were almost impossible to get, because even in the Zelmer they were not in stock. Eventually they appeared in the zelmer and I ordered them directly from the zelmer.
On the other hand, the quality of, for example, the material from which the base is made is pathetic because it turned out that under the paint, the paint is oxidizing, the paint comes out, etc. It is some university and they painted it

Pitt822 · Answer

OK, I'll twist the block and check it carefully. Certainly not between the halves, the leakage is from the bottom of the boiler, where there is already an exit to the flask.

--------------
Leakage at the bottom of the block. Need to replace this oval gasket (where can you get it?) Or try descaling and screwing it on again?

I am posting the photo because I was looking for it everywhere and it is not there, so it will be useful for internet posterity

Added after 27 [minutes]:

Tommy82 wrote:
I know a terrible crap because I had it.

On the other hand, the quality of, for example, the material from which the base is made is pathetic because it turned out that under the paint, the paint is oxidizing, the paint comes out, etc. It is some university and they painted it

You're right, the same relay that burns to everyone, they probably specially gave it to be an emergency. I put on stronger and it is calm.
I have this coffee machine for free, so so far I have invested PLN 15 in it (seal and relay) for 1.5 years of operation

There was also some peeling off paint under the strainer near the portafilter, clogging it, and blisters.

The cause of the leakage is likely to be these blisters at the interface between the blocks. Tommy82, helped polishing and leveling it?

Tommy82 · Answer

For me, the failure was in the buttstock socket at the bottom and it was a cavity, so I got rid of it to the flat one and the buttstock reached a bit more to the side.
I really don't know if sanding will do something good, I'm not even sure if it will turn out well after sanding in this place. There may also be some puffs under this seal and it escapes from there.

Pitt822 · Answer

Well, unfortunately, it also escapes from the upper block because a lot of these inequalities have arisen as it turns out after dismantling the block. Apparently his time has run out

robert_xyz78 · Answer

Hello, is there a graphic somewhere showing all the items mentioned in the manual? The espresso machine has just stopped working - no water (from the head and frother) and I would like to take it apart.

Pitt822 · Answer

It's just a pump that fell, I think, and you don't have to undress too much, just unscrew the back and remove it by pulling the hoses and unscrewing it. As I watched, there aren't many blue ones, I don't remember which producer, but you can probably replace a UKLA with similar parameters and the same outputs.

robert_xyz78 · Answer

Thanks for the answer. I unscrewed the bolts from the back, but it seems to hold something from the bottom and I don't know whether to unscrew or pull something else (I'm afraid it will break). Could some pump link (shop / auction) or sample model I could ask? best regards

Pitt822 · Answer

There are also such plastic hooks, you need to remove by force, pry with a screwdriver, some wide so that it bends a little.

I do not remember what model of this pump was there, it says what power.
From what I can see on the net, the blue one is 47W by some CEME company, but see what you have and buy the same power and connections.

The blue one, unfortunately, is so complex that it is held by such metal paws and it is impossible to unscrew it and replace the springs, as in ULKAch.

I see on the Allegro there is one such auction number 7383424401, but check if you have the same number and if the pump is not working. If you start the coffee machine without a back and the pump will only shoot and not pump, it means it will. Of course, be careful because there is high voltage and don't put your paws on when it's connected

And to disconnect the hoses there are pins, it's a bit of fun to take them out and then insert them

robert_xyz78 · Answer

There were actually hooks from the top. I unscrewed it and everything looks fine. I connected, there are no leaks, but in fact either the pump or the hose is blocked because it starts up but the water does not fly (video attached). How to check if the pump works well so as not to buy a new one for no reason? [Film: 88bc5c6cc1] [/ film: 88bc5c6cc1]

Pitt822 · Answer

I see you have Elka, you can take it out and unscrew it, I suppose the spring inside the pump has broken. Just be careful when disassembling because there is a tiny glass ball that is easy to lose and remember the order in which it was folded and where the ball should be on which side.
Watch YT videos first, there are a few with different types of pushups. e.g. https://www.youtube.com/watch?v=DoO9ckyJ-rs
It's best to find a movie where someone undresses your model, I don't know what you have, but it is written on the pump.
For some models, you can buy parts (spring, seals) and replace, but I do not know if it will be cheaper to replace the pump.

robert_xyz78 · Answer

Thanks for the tips. You can even see two small balls in the video. Tomorrow I will disassemble the pump and write if it is actually a spring. best regards

robert_xyz78 · Answer

I checked and I have a ULKA pump, model EFM type EP5FM (230V 40W). I've disassembled it into small parts and everything looks fine (no spring is broken). How to check if the pump is damaged? i.e. I would like to know if it is a pump or pump control (water is not sucked into the pump from the bottom)?

Pitt822 · Answer

Well, the water is coming from the bottom, connect this hose and you will see if it spits water / air when you put your finger on it. And you will feel if it works at all, just watch out for the electricity, do not touch the cable with your finger

Maybe this thermal switch on it has broken, you have to look for the cause.
In mine there was a burned relay on the PCB and it did not turn off the heating, but it has nothing to do with the pump. Anyway, check it if it melts, because they often liked to break down because they put it too weak (deliberate aging of the product).

MARCIN.SLASK · Answer

It is a pity that before disassembling the pump you did not check whether the pump itself draws water and pumps (as the predecessor wrote). Red ULKI are quite durable, unlike the blue / gray replacements, which were also installed.
The cause may be, for example, limescale blockage.

robert_xyz78 · Answer

It does not seem to be puffing water because the water hose in front of the pump is empty (dry) every time you try to start it.

Pitt822 · Answer

and did you connect the water tank? Maybe the coil in the pump burned out, if you have the meter, check if there is a break.

robert_xyz78 · Answer

Yes it is clear that I connected the tank and there was a place to get water. I wonder if the fact that you can hear the sound of the pump (as in the movie attached earlier) can clearly indicate that the pump or control are damaged?

dj_locco · Answer

And what, buddy, did you manage to figure out what was the cause? I am asking because I have the same problem.

robert_xyz78 · Answer

Yes, I visited an electronics friend and found out that descaling with vinegar sucks and everything is clogged. A friend decalcified, recommended kamix for cleaning, and it works until today

tomwoz · Answer

And I had a problem that the coffee machine started to leak. Unfortunately, the leak is invisible. As I disassembled the thermoblock, the longitudinal gasket that was visible in post # 5 is in a poor condition. I managed to get one, even the original one, but unfortunately it continues to leak. And I bet the reason also in what appeared above, namely inequalities in the place that adjoins the gasket on the other side, and is visible in the photo here:

I polish it up, but it doesn't seem to be of much use. Is there any patent for it ?? Because I have a brave idea to plan both parts like a head in a car - I wonder what they will say in the workshop for such a job

But maybe there is a simpler way? Will you suggest ?? We can omit the issue of profitability and labor consumption - I already have a new gasket, I make it for myself

sebkuk2 · Answer

If there are unevennesses, sand it gently and with black silicone to the engine blocks resistant to high temperatures, give this seal a twist and nothing will be leaking silicone seal is exactly a small hint for posterity I am playing in such various repairs, nice to everyone.

Zelmer Maestro 13Z012 Coffee Machine - Persistent Leak from Heating Block Post Gasket Replacement

Why does a Zelmer Maestro 13Z012 coffee machine keep leaking steam from the bottom of the heating block after the gasket has been replaced, and what part should be repaired or replaced?

Kawa i Naprawa - Serwis AGD

Topic summary

FAQ

Quick Facts

Where does the Zelmer 13Z012 usually leak?

Which gaskets can I replace without buying a new thermoblock?

Where can I buy the hard-to-find oval gasket?

Can sanding the block faces stop the leak?

What if pitting is too deep?

When should I replace the entire thermoblock?

How do I quickly test if the ULKA pump is alive?

Why does the pump buzz but no water flows?

Which replacement pumps fit the 13Z012?

How do I open the back cover without damage?

Is descaling with vinegar safe?

What electrical faults are common on this model?