# Do I need new seals?



## gwing (Jul 17, 2017)

Summary - I'm not getting as large a shot volume as I expect and wonder if I need new seals for my Quickmill Veloce, maybe the modified Londinium seals as the machines share the same group?

I'm actually getting nice tasty shots at the moment, if a little sharp (not sour) using barely rested med/dark roast 75% Costa Rican/ 25% Sumatran which is admittedly a bit on the bright side.

I'm running 18g nicely distributed grounds in an 18g VST basket ground fairly close to choking the machine and well distributed. As a test trying to get the highest shot volume I can I give it a 20 second pre-infusion to saturate the puck (this actually takes it to the first drop of extract only so is probably not 100% saturated but as long as I want to go). Pour is lovely and even through the bottomless portafilter running for 35 seconds before the pour finishes naturally giving me just 30g of extract after all the water is pushed through. Puck is left wet with just a tiny bit of water still on top - even after waiting 30 seconds before removing the portafilter.

Now I appreciate that normally we would pull the shot rather than leaving it to full extraction but even at the end of the pour it hasn't really blonded out and even the remaining drips taste sweet, in fact sweeter than the full shot instead of bitter, which make me think the extraction is not complete. I can't really grind much finer without choking although I guess I could drop down to 16g if I had to, but I'm wondering if the base problem is leaking seals which I should replace before experimenting much further. The machine is a couple of years old and I'm told hasn't had a seal change yet (except for the portafilter gasket). The lever does grab at about 45 degrees though so I don't seem to be suffering the same sort of slippage as described on the Londinium forums.

As a bonus question for anyone who might know the machine well (otherwise I'll give BB a call): the rather skimpy instruction manual states boiler pressure should be 1.2 bar yet mine's at 1.5 when up to pressure. Is that too high and worth adjusting?

Edit: I just ran a 16g shot with the same ground. Pre-infusion just six seconds as it started to drip through substantially at that point, pour was considerably faster and I got 40g at end of pour after 25 secs. Still tasting nice at the end though and I think still not fully extracted, It seems difficult to believe that just 2g of coffee could soak up that 10g difference of water though so maybe the seals are leaking while it is held in the longer pre-infusion for the 18g shot?


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## 4515 (Jan 30, 2013)

I replaced my Londinium seals at 2 years old and they were ready for changing. The rubber had hardened compared to the new seals.

The difference in operation was noticeable, post change. Far less grab, although I hadn't noticed the grab prior to the change


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## espressotechno (Apr 11, 2011)

1.5 bar is too high - it's too close to popping the boiler safety valve. Also the higher HX temperature due to 1.5 bar could result in the coffee in the PF being "burnt".

Reducing the pressure to 1.0-1.1 bar should give a sweeter brew, without losing any steam capacity for milk frothing.

If a new seal hasn't been fitted for a few years, you could fit a Cafelat E61 silicone group seal: Longer lasting, softer closure.


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## gwing (Jul 17, 2017)

espressotechno said:


> 1.5 bar is too high - it's too close to popping the boiler safety valve. Also the higher HX temperature due to 1.5 bar could result in the coffee in the PF being "burnt".
> 
> Reducing the pressure to 1.0-1.1 bar should give a sweeter brew, without losing any steam capacity for milk frothing.
> 
> If a new seal hasn't been fitted for a few years, you could fit a Cafelat E61 silicone group seal: Longer lasting, softer closure.


Thanks, that was sort of what I expected on the pressure - now I need to find out how to adjust it .

I replaced just the group seal on getting the machine as it was rock hard and had cracked, tried the Cafelat silicon seals first but on the Volece that turns out to be far too thick with the OEM ones being half that of standard E61. Following WD's likewise helpful post I've ordered in a set of the Londinium piston seals and will see how they go - if the current ones are as hard as the group seal was they'll be almost completely useless I'd imagine.

But that all said - the coffee tastes great


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## rob177palmer (Feb 14, 2017)

@gwing - just searching for fellow Veloce owners and stumbled across your thread!

Just closing out my first week, and I had a few questions, which you might be able to help out with, please?

1) did you find out how to adjust pressure? Mine is at 1.1 bar but I tend to only drink espresso so wondered trying a nudge lower.

2) does yours have any sort of low tank volume alarm system? Mine keeps running dry without notifying me!

3)how long do you find us needed for a cooling flush after warming up in a morning? I have been flushing 100-150 ml, but still see steam exiting group. I tried a super long flush this morning - wasted 1l of bottled water and still had steam out of group, so that's clearly not a reliable measure.

Help appreciated!

Rob


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