Hi, I have (or had) a rather incontinent Achille which leaked from the boiler to pressurestat coupling underneath the boiler when the machine was a little choked. (i.e. extraction barely starting or very long extraction requiring heavy force on lever.) I found that wrapping the ball joint and thread of the pressurestat inlet in PTFE tape stopped leaks when using reasonable force, but can still leak with a tight basket. I found that loosening the grind, updosing and using a 30-40lb tamp gave a good extraction without busting any seals or blood vessels. I found I would know if the grind was too tight within the first quarter of a pull. If this is the case, stop pulling for 10 seconds and the pre-infusion should penetrate the puck and give you a more manageable lever. This way you should still be able to get at least a 1oz double and you wont have to bin those lovely fresh grounds.

Hi Stephen
There is no correlation between the leak you had from the pressurestat coupling and the HX /piston /lever, portafilter circuit. They are two totally isolated systems. Could the leak have been due to excessive load being exerted on the lever, physically causing strain on the boiler mount system and that pressurestat coupling? The resulting leak was boiler water, not water from the top holding tank through to portafilter. By altering the grind/tamp, you were effectively reducing the strain you were putting on the entire machine.

I found that wrapping the ball joint and thread of the pressurestat inlet in PTFE tape stopped leaks when using reasonable force, but can still leak with a tight basket.

Do you mean the pressurestat coupling "can leak with a tight basket" or a leak is occurring from the hole under the grouphead or down the side of the boiler from the grouphead? If the latter is the case then the o'ring at the top of the piston cylinder #16 is failing.

Hi Craig

Yes, sorry, didn't explain myself very well! I understand that the boiler is not affected by lever pressure and the leak under the boiler is probably due to the torsional force on the chassis of the machine rather than water pressure, but it is still neccessary to adjust the preparation of the basket to avoid this. I have had water leaking from the grouphead before but only after a curiosity rebuild. This was cured by seating the o-ring correctly as you say and greasing all the washers and gaskets.

In terms of getting a good cup from the Achille I found the only way really is to just keep playing with it. Get 1kg of good fresh beans, mop up the tears as you throw away shots which have choked the machine or channelled like crazy and within a few days you will be making the best cup you've ever had. The biggest turning point for me was discovering the Weiss Distribution Technique (always thought that was a rather grand name for shoving a yogurt pot in the top and stirring it!), this has improved things no end but I'm still only a few weeks into Achille ownership and things are still improving.

The biggest turning point for me was discovering the Weiss Distribution Technique

I never got into the yogurt pot thing, but did use the 'stirring' needle for a bit.
Ended up just dosing (not over dosing), tamp and pull. Works a treat.
Cheers