Greased Lightning wrote:My thoughts are that I need to find a way to quickly and accurately measure the brew water temp at the portafilter. Or maybe there is some trick with watching the steam with the valve open. Perhaps other Oscar owners can tell me about how long it should take for the heating light to go out from a room temperature start.
Measuring the brew temperature water won't give you an accurate indicator. Comparing the force and sound of the steam would give you a ballpark estimate of the boiler pressure. The boiler cycle time would give you a very rough guess too, but probably not within more than 0.3 bar, which is too wide a margin of error as a starting point for brewing espresso.
Greased Lightning wrote:I don't even know how sensitive the adjustment screw is....I have turned it several times over.
Would you post a picture of the pressurestat? The newer Oscars come with a Sirai pressurestat. Those have lots of turns to the adjustment. The Mater/CEME type pressurestats are very sensitive and vendors have mentioned that over-torquing them is a major cause of failure (and not covered by the warranty).
It would be best to actually measure the boiler pressure with a gauge, but that of course assumes you're willing to pay a certified repairman to install one, or have necessary skills to install one yourself (please insert standard disclaimer about the risk of scalding, explosion, burns, fire, and death here).