Opening a grouphead for the first time
by Bruce Colglazier Pappas
I decide to clean my machine today. I used something mild, Durgol Swiss Espresso Descaler/Decalcifier. It worked great. After it sat 30 minutes, I heated up the machine and ran the liquid through the group and the steam wand. The boiler looked great. I figured then that I might have some junk caught on the shower screen, so I decided to pull the group for the first time and remove the shower screen. I had been wanting to do this since I bought my machine 2 years ago.
So...2 hours later, it's back together and I pulled a shot. No major leaks, but the shot is too long due to the piston being properly adjusted. I'll explain in photos that follow.
First, the bolts that secured the group were not stainless. The fact that they had rusted on such a beautiful machine always bothered me. Luckily, I bought new stainless steel ones when I bought the machine. I had to use vice grips to remove the old bolts, as the heads were stripped and rusted.
Next, I found that the group gasket was flattened. Someone had used Teflon string to fix this. I'll get a new gasket soon and fix this properly. For now, I'll re-use the Teflon string when I reassemble. (Note: it leaks a little from here now, but not enough to stop being used. This is a new leak.)
Next I pulled the PF gasket and screen. It was easy using the hooked tool. And the gasket came out undamaged. I found some gunk inside the screen, but less than I thought I'd find.
Then I found what I thought I'd find, based on the year my machine was manufactured (2005). I DO have a Teflon piston and a Teflon sleeve.
So off came the handle and out came the piston. The sleeve is in good shape, so it appears.
Upon examination of the piston and gaskets, I found one gasket is damaged. It looks like whoever did the rebuild didn't get it in right and it folded over itself. Thus, why I have a leak from the group. I thought descaling had damaged these gaskets, but that was not the case. Both gaskets were in good shape, except for this one fold.
My plan is to replace the Teflon piston with a brass one soon, so I'm not too worried for now. I'll replace the gasket then, too.
I cleaned the fill tube with a brass bottle bristle brush. There was little inside, but it was good to do a good cleaning.
After a good cleaning of all parts, I lubed up the piston, the gaskets, the piston arm, and sleeve with Dow Corning Molykote.
I reassembled the piston, the group. and handle. I had to pay special attention to get the folded gasket back in right. I had previously purchased a series of washers to be used as shims, so I could take the play out of the handle. I inserted 3 roller bearings and a few washers. I'm happy with how much tighter the handle is now.
Another thing I'm interested in is the throw of the handle and piston. I adjusted it to its maximum and tightened down the capture nut and cap nut.
I was surprised by how much looser I could make the nuts to get the maximum throw. I think I'll be able to get more water in the chamber now.
With the machine back together, I found:
- The piston works much easier since I lubed it. Yes, I still need to replace gaskets.
- With the lever throw properly adjusted, I get much more water in the group and more liquid out. Not too sure how much, but I used to only get 30ml. With a Fellini, I'm sure I can get 40ml or more, but I'm not sure that I want that much!
- The handle is much tighter and doesn't move as much side-to-side. The washer shims work great.
- I have a small leak where the group attaches to the boiler. I need to replace that gasket, or install a Teflon gasket to isolate the two, as I have been planning to do.
Just one of those days where I started out to just clean the boiler and end up doing exploratory surgery. When I do this next time, I'll pay more attention to how water enters the group. I think the water enters through these 2 holes.
Thanks for reading my story. I wonder how these adjustments will affect my routine and what changes I'll need to make.
Created 30-APR-2017 | updated 07-FEB-2023 | BCP