Absolutely, it is very likely stuck, but once the hex screw is loosened sufficiently, you simply unscrew the entire steam valve knob counter clockwise. It will come out, and there is a separate valve stem inside that will fall out if you aren’t paying attention.
The hex screw may have simply fallen out, because the machine was designed for it to be there.
Well, you can’t remove the 4 hex bolts in this way. first you have to remove the 4 crown hex bolts first on the exterior of the machine, where the Portafilter attaches. At this point, you can separate the boiler from the frame. Now you can use an 8mm bit driver, in combination with an 8mm wrench on the hex nuts, to separate the boiler into its individual parts. The details are important.
AAAND…. now your link is broken, Rich. So now we go to, you guessed it, ifixit!
Schematic and Troubleshooting Starbucks Barista SIN 006
A well thought out repair. However, the internal part that needs to be replaced is actually part number 9, which is the actual gasket for the steam valve plunger. I’ve done this on my old Saeco Barista and it worked well. My machine is 16 years old and the boiler works like a furnace. These are excellent machines.
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