Rocket Appartamento pours really slow - brew pressure or pump problem?

[TheGovan]

Long story short, I am a newbie to HX prosumer machines and I purchased a used Rocket Appartamento a few months back.

My curve has been learning to dial in espresso. I also purchased a used Rocket Fausto grinder and have been very happy with both.

My concern is that as I have had to grind the coffee finer for more extraction, I find the Rocket HX unable to deal with pushing the water thru the puck so sometimes I get an espresso shot lasting more than 30 seconds or literally just drips of coffee. At this point, I'm not even tamping very hard. I'm using 18 grams of coffee in an 18 gram basket.

I've never checked the brew pressure (nor do I currently have the means to) and I doubt the previous owner ever changed it from the factory setting. I'm worried that either the vibration pump is not up to par or the E61 grouphead needs maintenance.

I'm in Houston, so I'm not sure if there is even a technician or repair site that services Rocket. Which means boxing it off and shipping it for a diagnostic check.

OR is this typical, and should I be tamping much less, or grinding less but having to deal with sour espresso??

Your advice is much appreciated.

[lessthanjoey]

No need to grind ultra fine, you're likely just making it worse by channeling and reducing evenness.

Just increase your ratio to increase extraction... Instead of 1:2, try something like 1:2.5 to start with.

[stefano65]

There are plenty of E-61 HeEx with a vibe pump,
even when the 41W was standard before switching to the 52W ones,
check the OPV and see if opens where it should, 9-10 will do.