jackhk Do you guy’s have any clue? do I missing something 🤔
In the video, the machine is working exactly as it should. If the pressure gauge was dropping before, it’s because you had a very small leak or leak back (though the one way valve) in the sealed brew circuit…this was allowing the pressure to drop.
When you do a shot, the pump introduces about 90 ml of cold water into the brew circuit…when the shot stops, especially if it’s not a really long shot..the water in the boiler is still heating and expanding. If we make the assumption that after the shot the water in the boiler is still heating perhaps by a few C, then the expansion in volume might be 0.5 to1ml. This is enough to raise and maintain the pressure. If there is even the slightest leak, this would drop rapidly to zero.
Why the Mara drops immediately to zero and always does, is because there is a solenoid to vent the brew circuit….for no other reason than to drop the gauge to zero…A feature that really holds no benefit.
You do have another problem though, the lever stem is leaking (I saw it dripping in the first video), this can be for a number of reasons, you will know which one it is:
- As the seals on the stem age, they can start to leak
- The lever stem and inside where the stem goes (use cocktail stick) are never lubricated when the lever is removed to lubricate the cam (which should all be very dry or it slides off)
- You have never ever removed the lever to lubricate the mechanism
Replacement seals should be very cheap.