First off, my apologies for the cross-posting if you've seen the first part of this before elsewhere; when asking elsewhere I got a bunch of feedback that this was the right place to be asking about this class of machine, and based on some time reading here I can see why!

I have a new-to-me CMA (Rio) SME/1N JUN that seems to mostly be in good shape but on which the right-hand side of the boiler looks fairly bad, in particular the brown... stuff (growths? deposits?) next to the sight glass guard. The boiler holds pressure, but I'm wondering if this is a sign of pinhole leaks and impending doom, or whether I should clean the machine up and get on with life. (I can read manuals all week, but this one needs a bit of judgement!) Anyone?

Also, thanks to all of you that have posted the amazing and picture-laden threads on rebuilding your CMA machines; I got this machine almost on a lark (one of those "right place at the right time" deals), but I think it's a keeper, and it's nice to see what I'm in for if I do end up doing a complete teardown. (Actually, most people seem to be dealing with SAE/1N machines instead of SME/1N, but I haven't noticed the difference. Do this acronyms actually mean anything?)

Thanks for any clues/advice/observations/mockery/inspiration!

Randy G. wrote:I recommended pulling the heating element in the other forum where the OP placed a similar post with the same (but smaller) image.

Indeed, HB has much more useful limits for image size! (Also, thanks for the recommendations in both cases.) I've attached the element picture (though it's not inline) in case it's useful, but it looks just like a heating element should, I believe. (The element itself looks great to me, with just a bit of wet loose scale picked up from the gunk at the bottom of the boiler as I took it out.)

The boiler looks less good, but maybe not disastrous:

Getting in there for pictures is a bit difficult; sorry about the quality. From where things are now I can easily enough vacuum out the main boiler, but if the heat exchange chamber is also likely to be crudded up I may as well have it all out now and turn this into yet another CMA rebuild thread. From my explorations of the solenoid area I'm already planning on having the group out for cleaning, so I've given up on having this in operation in the immediate future.

Chert wrote:Although I've not been around enough commercial machines in prolonged use to be very knowledgeable, I think there has been some leaking water from the fittings.

The machine is basically also open on the top aside from a grating, so if the previous users were in the habit of putting wet cups or whatever up top to warm, it would all also be dripped down into the works.

BTW, What is the material fitted behind the sight glass? I want to contrive such a thing for my ongoing CMA restoration.

It's enameled steel, I believe. I'd first taken it as a stock part, but looking again it's clearly a somewhat sloppy but surprisingly useful retrofit that happens to wedge into place nicely. Here's a picture (again sub-par, I'm afraid) of it from the front; note that unused screw holes that were clearly intended to mount it on something else:

cannonfodder wrote:If you had a way to pressure test the boiler I would do that before spending all the time working on the rest of the machine. Pull the boiler, descale it which will take quite some time from the looks of it, then pressure test it to see if you a big door stop or a rebuildable machine.

That's fair; thanks for the input. My irrational optimism (and perhaps laziness) aside, it's only a half-dozen more fittings, and a pressure test after that is easily done and should remove all doubt.

Based on other repairs I've seen here I'm hesitant to assign it doorstop status just based on boiler leaks, though. Actually, there doesn't seem to be much anywhere on these machine that isn't fairly readily repairable, though if the boiler needs repair I expect I'll be seeking professional help.

For reference, here's some useful advice on boiler repair in this thread, both some less-recommended but possibly effective techniques and suggestions for the right way to deal with it: Repairing leaks in a copper boiler