Here it is installed and currently under testing.



Upon further testing noticed thread on adapter is too long and makes contact with the top of the site glass.
Further tightening is required in order to form seal but also presses down on top of site glass.
Crushed top of sight glass which caused fracture one third down.
Not my sharpest day as it cost me two glass tubes before I figured it out.
I ended up cutting threaded stem in half. Problem solved.

So,I got some sight glass. Had some thick 1.5mm wall cut at a lab supplier.
Not only less expensive but better than the <1mm wall common replacements.



Poor photo due to the "one handed technique".


New site glass installed and passing 3 cycles so far.

Having mounted 6+ sight glass adapters and pressure gauges to 1st generation La Pavoni Europiccola machines I've noticed something interesting.

The addition of the adapter and oem length of the glass tube invariably blocks the upper sight glass return. This either entirely blocks or mostly covers the return port causing a vacuum in the tube preventing air displacement until enough pressure is built up to push the air through with water. Noticed when water was added to boiler it did not enter the tube until pressure built once boiler was closed.

The fix is to cut the tube between 128mm-129mm opposed to the oem 132mm-133mm.
The same oem thin tube cannot be used if replacing with new silicone sight glass seals as they require the thicker o.d. tubes, regardless if adapter is being installed or not.
I was never keen on the oem thin <1mm glass tubes anyway and prefer new laboratory supplier grade low-thermal-expansion borosilicate glass with a wall thickness of about 1.5mm.