 Replacing E61 grouphead seals - DIY diary!
OK, so there's been a few indications that things aren't working that well
with the Isomac but you don't want to take it apart or worse still take it
somewhere else for someone else to work on...
Several weeks ago...
notice water dripping from gland nut of lever shaft. Yes, definitely
seeping out when a shot is brewed. Do google search on water leaks and ask
questions here about replacing seals. Get answers - easy job by the sound
of it. Do a backflush and miraculously the leak stops. Thinks to self that
it probably won't last but still put off getting parts etc.
One day last week...
Could of sworn I saw a drip or two out of the bottom of the valve into the
drip tray while pulling a shot. Brew pressure wasn't too bad but suspicions
are deepened. Espresso was still pretty good. Maybe it was a trick of
the light. Note that there was an annular eclipse (but not in NZ).
The day after that...
Not at all convinced things are working properly. Brew pressure doesn't
seem to be right. Espresso still quite acceptable though. Decide to do
backflush again. Aaagghhh, pressure ramps up, hits 11 to 12 bar and gushes
out bottom of valve in to drip tray. Not happy. Begin mental preparations
for strip down.
6th October...
Look for diagrams of E61 group on web. Find some, also get cool info from
coffee people. Still use machine to make a pretty passable espresso.
7th October...
Day off work. Decide this will be the day for the repair job. Turn the
Isomac off.
Armed with diagrams etc, go to Espresso Engineers and get seals. Return
home and begin taking things apart.
Not really that hard.
Discover a small amount of gunge inside but cleans off OK. Seals are all
very hard and useless. Decide that there must be a special tool (like a
hook or something) to remove the valve seals - use a pointy sharp thing (I
could be more technical) and manage to remove them, only once stabbing my
finger in the process (much blood).
Find that seals for lever shaft are wrong size (they warned me things can be
a bit different to the drawings etc). Thwarted, as its now around 7.30pm.
Hope that they may be open on weekend to do a swap.
No coffee. Very sad.
8th October (today)
Ring Espresso Engineers, get answer, yes they're open. Zoom into town with
offending bits (40 km round trip). Seals swapped.
Back home, continue with reassembly.
Replace the 'O' ring on the top jet assembly (not sure what its actually
called), looks very fat. Try and insert it into to group but its way too
big and will not go in fully to allow the thread to engage.
Thwarted yet again. Its 3pm now. Wife has the car. Resign to not being
able to complete the repair until next week. Very sad. So close yet so
far.
But wait! The garage door opens, she's back!
Ring Espresso Engineers. Yes, they're still there. Zoom into town etc.
(with parts, get the right sized 'O' ring).
Return. Complete the repair. It all goes together easily.
Fill tank with water. Switch on. Get rid of air lock. Allow to fully heat
up...
Somehow I manage to wait a full 3 hours before testing.
Grind, tamp.
Oh my, doesn't it work well. I haven't seen it pour like that in ages.
All seals obviously doing their stuff.
The espresso is not just good, it was awesome. I had to have another.
Which is why I'm still awake and writing this.
In retrospect, what I should have done was take it to bits first, take the
bits to Espresso Engineers and got all the right sized replacements first
off (as I mentioned before, they did say that sizes can differ).
I was happy with the quality of the espresso I was getting before doing all
this. Other people agreed. But whats interesting is that I am sure that
the espresso I've had tonight is higher quality than I've had from it for
months. The pour was slower and darker, the preinfusion took longer before
the pour began. Basically it appears that the machine is working way better
based on the quality of the espresso - more so than I would have imagined
just replacing the seals could achieve. But not that I'm complaining! I
figure it is worth changing the seals earlier next time (ie before any leaks
occur).
Derek "hooray, I've got espresso again" Hobbis, and sorry it ended up being
a bit long...
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