If you own a e61 espresso machine you have undoubtedly heard about the debate about how often you should backflush.
In my case, I tried chemical backflushing on a new machine that was less than a month old. Sure the group pathways were cleaned but the machine seized up so solidly that a two handed power lift of the brew lever could not even actuate the microswitch. In a testament to fine Italian engineering, I managed to lift the front-end of the machine clear off the counter with the brew lever. The resulting parody with vicegrips and delicate brass parts best not be repeated here other than to say, it was not a pleasant experience.
Shortly after, I joined the camp of water backflushers and soon became a front flushing disciple.
Amazingly, the group gasket lasted 4 years of daily use – still sealing perfectly but the portafilter was starting to slip ever so slightly out of the group when backflushing. Time for a new gasket.
How difficult was it to remove a 4 year old group gasket?
Despite the horror stories of chiselling out a carbonized gasket, amazingly, a very gentle pry of the filter screen (with a blade screwdriver) was all that was needed to pull down the filter screen along with the old gasket.
What I saw was appalling. The filter screen was encrusted with a black, crusted on burnt layer of some alien origin.
[Note: I would have liked to have included a picture of this abomination of nature, but somehow the filter screen was nicely washed in the sink before I could grab for my camera].
Inserting the new gasket was much more difficult. Do not bother with the trick of putting the new gasket on a portafilter ( without the filter basket). It just won’t work until the new gasket is almost bottomed in the groove.
The best way is to gradually work the group gasket into the groove with your fingers and then use some sort of blunt tool to push it into place. I used the plastic handle of a group cleaning brush for this purpose. Once it is in the groove, use the portafilter with a filter basket to crank it fully into place.
Next time I’ll try using a food grade lubricant (Dow 111) on the gasket and see if that will speed up the process a bit.
Does backflushing with plain water accomplish anything useful?
Possibly. It will do a decent job to keep the underside of the “bell” and filter screen mostly free of coffee grounds but that appears to be it. Still worth doing except I would recommend incorporating the removal/cleaning of the filter screen as a regular maintenance item.