I'm tinkering around 1979-1980 La Pavoni Professional. I pulled out the piston and this is the internal grouphead:



I never saw the internal of the La Pavoni grouphead, but this one seems without the sleeve. Am I right?

Yes, that is a version 2 group with no sleeve.

The version 1 group has a brass sleeve, and the version 3 (millennium) group has a plastic sleeve.

Thanks!
I didn't know La Pavoni made this kind of group.

BTW- How is it compare to version 1 and 3? Or is it "to each his own" case?

And- is the piston the same as 1 and 3 version?

I can't say for the version 1, but it does have the same piston as the current version 3 group.

The sleeved groups have are water heated, and the V2 group is steam heated. The steam heating makes temperature management a bigger issue in the V2. Regardless of which group you have I recommend a group thermometer (either temp strips, or a digital thermometer with a thermocouple).

There is a mod, "the Bong Isolator," that converts the V2 to water heating that you may be interested in.

Note:

I have a v3 millennium machine, and no need for a Bong Isolator. So, I have no direct experience with a V2 machine, or that device. Still, the group temperature control is a known issue with V2 machines, and there are many methods for dealing with it. All of them require some kind of thermometer to hit the sweet spot for extraction.

I will check into that.
I appreciate your input on that matter.

This was just posted in another thread on the "Bong Isolator," and it looks like a much better idea to get the same benefit:

Whats the verdict on the Grouphead/Bong Isolator for La Pavoni?