Soupy pucks and low volume

Ben Hill

Hey all!

We've had our L-I hooked up for about 2 weeks now, and have finally had a little time to start experimenting with it. On day one we just shot from the hip, without measuring super carefully, used a crappy grinder, and the shots weren't perfect, but they still tasted decent and the pucks were dry.

Since then we've gotten a better grinder and had a couple of "practice"sessions. The first few shots we pulled were pretty decent, but as time went on it seemed harder and harder to pull a good shot.

At this point, every shot we pull has a really wet puck, I mean almost soupy on top. The extraction volume seems low too, although I haven't measured it. It would make sense though, because half the water is still in the portafilter!

I'm not sure what we're doing wrong. I'm measuring 15.8 grams of beans and have tried varying degrees of grind, and varying amounts of tamp pressure. We're pre-infusing for a slow count to 6, then pulling up until it catches and letting go. We also make sure that pressure is right at 1.3 bar before we pull.

I'm sure there's something we're missing. I'm wondering if there's something on the machine that I should be checking/maintenancing. Any suggestions would be greatly appreciated.

Otherwise, we love the machine, and everyone comments on how beautiful it is. Can't wait to get these shots down and start serving!

Robert Hall

Ben, I bet you are having the problem that I had recently after about 2 weeks. When you raise the lever to pull the shot, at what angle does the lever engage. If it is engaging at about 45 degrees it's not the same problem. If it is engaging much higher you prob need the new custom seals.
Rob

Frans Goddijn

Ben Hill post=11807 wrote:
I'm not sure what we're doing wrong. I'm measuring 15.8 grams of beans and have tried varying degrees of grind, and varying amounts of tamp pressure. We're pre-infusing for a slow count to 6, then pulling up until it catches and letting go. We also make sure that pressure is right at 1.3 bar before we pull.

I'm sure there's something we're missing.

What beans are you using? Do you know the roast date? Can you measure what weight extraction exactly comes out in how many seconds?

As said above, knowing at what point the lever 'catches' is also important.

If possible, a video of your routine and extraction (filmed horizontally).

Reiss Gunson

hi ben

thank you for posting in the owner's forum, as everyone benefits

it is good that you have upgraded your grinder and are weighing the dose

as rob suggests, you may well have the same issue that he and a number of owners have been frustrated with

note that the issue will arise in all machines that utilise this group

if so i have documented the interim solution already on this forum; simply remove the bottom most piston seal carefully and wrap perhaps 7 or 8 turns of ptfe thread tape, as used by plumbers, carefully around the seal groove. try to lay it on smoothly with as few creases as possible

the permanent solution is our high performance seals, the first 50 of which arrived on friday and will all be used to fulfil back orders, and the balance of which will arrive this week

alternatively, you may simply be grinding too fine. if you grind too fine the puck becomes impermeable at boiler pressure (the pressure at which pre-infusion occurs) and then when you release the lever and the much greater pressure of the spring is applied to the water, the water drops into the dry puck causing the lever to grab high and you are left with a wet puck

try lengthening the pre-infusion to 10 or even 12 seconds perhaps and see if that improves matters

kind regards

reiss.

Ben Hill

Thanks everybody for the thoughts and suggestions.

The beans are from a local roaster, only about a week old.

When I'm up there tomorrow I'll pay more attention to where the lever engages. I suspect that it engages higher than 45 degrees. I'll also weigh the extraction amount.

If it is the seal issue I can try the interim fix. Will all L-1 owners be getting the new high performance seals eventually?

I'll also try a longer preinfusion and see if that makes a difference.

Thanks all, I'll report back.

Ben Hill

Did some more tests yesterday. The lever is definitely grabbing higher than 45 degrees. I'd say it grabs around 25 degrees.
When I do the longer pre-infusion I'm getting about 40 grams in the cup if I catch the whole thing.

I'm guessing this means I need the new seals?

Thanks,
Ben

Ben Hill

I think I would like to try the interim fix with the ptfe tape. Is there a link to a step by step for this fix?

Robert Hall

Ben,
I did the fix with the tape. It lasted a few days, and it is back to catching high, although not quite as high as before. Reiss recommended 8 wraps, and the seal stuck way out. I ended up doing 5 wraps. This is what Reiss sent me:
Rob

the task is basically a seal change and the video for that is here;

londiniumespresso.com/forum?view=topic&catid=27&id=743

note that you will need to be logged in to access it as it is in the permanent file section of the website

you only need to do the bottom seal, so obviously you can ignore the steps that relate to the middle and upper seal

in terms of applying the ptfe tape the only requirement is to wrap it on as smoothly as you can. the width of the ptfe tape will be wider than the groove in the piston so expect the tape to wrap up the sides of the groove a little