For now, I just muscled the spring so it is a little closer to the original shape. With the p-stat adjusted to the highest pressure setting, I can now get water at 204F measured at the bottom of an empty portafilter basket. The cycle times are about 1m10s at temp (light off) followed by 18s of heat.

Without a proper pressure gauge, am I at roughly the right settings to begin playing with it?

Probably yes. It's nice to be able to go a touch hotter for light, acidic roasts. If you shorten the tab to the microswitch you should have the full adjustment range. Or, if as Rich suggests you can remove and change the spring that could help. I don't know if the spring is easily removed because Doug Garrott would have shown how to do so.

drgary wrote:Or, if as Rich suggests you can remove and change the spring that could help. I don't know if the spring is easily removed because Doug Garrott would have shown how to do so.

I tried to remove the spring but it wouldn't budge from the top screw. It looked like I'd have to destroy it to remove it.

Without having it in my hand I can only guess how it is attached but the usual method is the screw is threaded into the spring and once and awhile they are then soft soldered. The fact that it is mangled is indicative of a previous removal attempt. Proper repair will require obtaining the counsel of someone who has disassembled one of these.

If this was my machine I would purchase a new PS and put that one into the box labeled "OEM Parts To Be Restored" and wait until I find someone local who is willing to take on a project like this.

Accomplishing the feat of pulling espresso without much fiddling requires the hardware is in proper working order. A big pat of this is the machine is operating at the proper pressure AND temperature. These machines are saturated steam systems and will not function correctly if it is not operating at saturation conditions.

Known pressure, narrow dead band, and noncondensables properly vented are basic requirements.

In took a different approach-i rotated the microswitch clockwise a few degrees so the right mount screw is no longer in the original mounting hole. Instead, it now touches the bottom edge of the pressurestat.

In the photo I've got it set so the water out of the empty portafilter is 202F and there is plenty of room for adjustment. I think I can finally begin to play with it.

I'll be interested to see if that works.

As a reference, here's a rebuild of a similar, slightly older Olympia pressurestat.

And, as Rich wrote above, if you can't get this pressurestat working it's easy to swap in a new one.

I suppose I need to get a pressure gauge to know for sure. At the moment I'm just measuring water temp out the bottom of an empty portafilter. But the results seem to be consistent, if not accurate.

You could test it two ways without a pressure gauge, although connecting a pressure gauge to the steam wand isn't hard.

The Livietta/Maximatic is a dragon HX. With the proper pressure setting, the water at the group should start too hot for everything but a very light roast. You flush the group to cool it. If the water sizzles while coming out of the group it may be hot enough. So listening for that sizzle is one test.

The next test would be to get a light roast and see if the brew temperature is hot enough to tame the acidity. This would have to be a light roast that can be brewed so it isn't harsh with the right temperature and brew ratio.

mixuala wrote:I suppose I need to get a pressure gauge to know for sure. At the moment I'm just measuring water temp out the bottom of an empty portafilter. But the results seem to be consistent, if not accurate.

Orphan Espresso used to sell a pressure gauge for the Cremina, but stopped selling them shortly before I acquired my Cremina. I spent a long time trying to find the exact parts to build one, both researching this site, parts sites, visiting parts suppliers, etc. It seems like this should be ridiculously simple. And once you figure out the sources for the three parts, it is. But it wasn't.

For the old style Cremina's like mine, I think it's worthwhile to have one of these on hand. I bought Cerini's version here and find to be a quality part at a reasonable price.

https://www.cerinicoffee.com/olympia-ca ... ified-cap/