Of my two Rancilio S27 I now have one working! ... now looking to get "parts" machine working.

First big concern is that the boiler lid has cracking. I guess this might have been caused by freezing. The heat exchange pipe is burst at the bottom... I think maybe it also go pushed sideways to create these cracks... when I got it there was a half tank of water in boiler... I don't think enough for ice to push against the boiler top, so that's why I think pushing on heat exchange maybe did it.

About the cracks:

1. They don't seem to go through to other side
2. They do go around outside ring, maybe 25% visible in total. I've focused on the worst looking ones, but you can also see more in lower right.
3. To my untrained eye they general appear to have a low angle, ie going shallow/parallel to lid surface instead of down into it.

I looked into getting a replacement top, but very expensive (~$250). I've done some searching in these forms and was happy to seem some complaints about actual leaks through holes in boiler... and fix suggestions with welding.

My question is what's a good next step here?

1. Should I just try it and see if there are leaks?
2. Should I take to welder?
3. Or maybe maybe there's something fatal about these cracks and I should give up?





Thanks,
Jesse

I am an instigator, but since you are an expert now:

https://nh.craigslist.org/app/d/derry-e ... 85265.html

I spoke to hom and there is a lot of interest. Its rebranded s27

The Laranzato was produced by VFA and Rancilio
both out of of production
I recall couple of models called
Ecco and Green
some of the parts for both are still around.

Coffcarl wrote:I am an instigator, but since you are an expert now:

https://nh.craigslist.org/app/d/derry-e ... 85265.html

I spoke to hom and there is a lot of interest. Its rebranded s27

Ha, no my goal is to get extra parts of our house and in working order... not get new spare parts! Hoping welder will say something is possible.

If you are adding metal to the boiler, keep in mind the lead (as in pb) factor. Brass normally has a lead component, and although it is the boiler, so the only concern is steam and water from the spout, you.might see if the welder can use naval brass which is lead free, or some other lead free material.

Are you sure that you have cracks? Since the brass is probably a sand casting I believe you are looking at flaws in the sand pattern that have shown up in the part as fins.
jpboyt

I have no idea, but I could certainly believe it.

I'm not sure how to tell difference between cracks and flaws showing up as fins. The pattern definitely is odd for cracking (again I say this without much knowledge) and again without knowledge I could certainly believe it's instead a part of the casting process.

This all brings up a related question... why are espresso boilers so heavily built in the first place? Or maybe the reverse question is why is the coffee dispense pathway so minimally built? It seems the coffee dispense pathway is supposed to withstand 9+ bar, while the boiler operates at a seemingly much less 1+ bar.

Maybe it's because of the much larger surface area in the boiler? Anyway it's surprising me.

I think this explains it in part. It does not have to do with the ability to withstand pressure, but rather, the ability of the copper to conduct heat to the grouphead:

https://dailycoffeenews.com/2019/05/29/ ... -espresso/

You are likely looking at flaws in the sand casting mold that appear when the molten brass hits it. If you are concerned then run a cold hydro that holds pressure for 24 hours then check for a leak. hydro at 2 bar nominal.

I think it is overflow from the sandcasting as well.
You may try to grind down part of the raised surface with sandpaper. If it is crack, you will see it clearly right after. If it is casting overflow, the surface will be nice and flat and your worries are gone.