# Pressure tweak on Gaggia Classic RI9403/11 (spurting)



## lmpedro (Oct 11, 2016)

Hello all!

I recently bought a the new model of the Gaggia Classic (Gaggia Classic RI9403/11), and after a few weeks of producing decent shots it started spurting coffee/water from below the portafilter after a few seconds. This happens even just with water (ie., without coffee in the filter basket). I looked around a bit and figured this could be due to excessive pressure, although it strangely only started to happen after a few weeks. The gaskets are all new.

So I'm keen to try and reduce the pressure, but it seems as though the internal setup of this model's different from the old one, for which there are a couple of tutorials, and I can't find where to adjust it. Does anyone have experience with this? Or if you think it might be a different problem/solution, also please let me know.

Cheers!

Pedro


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## Mrboots2u (May 10, 2013)

Have you changed coffee ?

Are you weighing the dose ?


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## jimbojohn55 (Jan 15, 2016)

Hi Impedro - I have the same machine the newer classic - I'm not 100% where you say the water is squirting from - but in my experience the following may cause issues

1 there is coffee grounds on the seal preventing it working properly

2 aftermarket bottomless portafilters don't sit properly against the seal

Re pressure - in my tests and others the actual pressure at the basket is actually 9 bar not 15 as advertised

there is a thread on the location of the OPV valve elsewhere in the gaggia section of the forum

http://coffeeforums.co.uk/showthread.php?21593-Poss-mod-no-goes-on-the-2015-Classic/page5

try page 5 of this for a pic of the new models opv valve

PS have you removed and cleaned the shower screen and while off unscrew the brass nut (flat screwdriver required) that's located under the shower screen - this will let you remove the spring with a silicon ball on the end - sometimes they clog up or don't seat properly.


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## lmpedro (Oct 11, 2016)

Thanks a lot for this, folks!

It can't be the coffee, because it's squirting even without coffee in it. I've posted a short video here showing the problem: https://www.youtube.com/watch?v=6RQLLr6itss.

I've also cleaned it properly, and am using the portafilter that came with the machine, so I figure it shouldn't be much of a problem.

What I haven't done yet is remove the brass nut to check on the spring (need a larger flat screwdriver than I've got).

I got a pressure gauge to measure the pressure, but now am looking for a conector to attach it to the bottom of the portafilter - which is proving a bit hard, because of the uncommon size.And thanks for directing me to the post that shows the OPV valve!

Any other ideas? Thanks again!


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## jimbojohn55 (Jan 15, 2016)

interesting video - the variation of pressure during the shot - I'm wondering about the following

1 check the ball valve once you get a bigger screwdriver

2 check to see if the plastic insert that the portafilter lugs engage with in the grouphead are not damaged - it seems to be an emerging problem with the later model

3 You using the basket with a single small hole in the bottom - the fake crema device - cast it to the four winds, - throw it into the fires of mordor or just recycle it but get rid of it - I think your issue is the pin in it is knackered - its a terrible invention - buy a standard 14g basket (vst if you can afford it) if not order one from ebay or espresso solutions.

I'm pretty sure 3 is the issue - the fake crema basket - easy fix - replace it

let us know what you find

Cheers Jim


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## lmpedro (Oct 11, 2016)

Oh, that might indeed be it... hadn't thought of that possibility, but now I'm pretty convinced it's the case!

Will go for the VST, then, thanks for the tip. Any suggestion on whether to get the ridged or unridged version?

Cheers!!


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## jimbojohn55 (Jan 15, 2016)

Ridged lock into the holder with more of a click as the ridge fits the holders spring- but the unridged will still be fine

cheers Jim


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## lmpedro (Oct 11, 2016)

Thanks a lot, mate! This was very helpful indeed... When I get the new filter basket I'll reply again telling what the results were.

Cheers!!

Pedro


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## Jumbo Ratty (Jan 12, 2015)

I just watched the video.

Like jimbojohn55 i think you are using the pressurised basket.

BUT it doesnt look like you're putting the fake crema pin (the plastic doohickey) in the base of the portafilter that is intended to be used in unison with the pressurised basket. The missing crema pin is the reason you're getting the mess you are.

This explains it all


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## Jumbo Ratty (Jan 12, 2015)

oh yeah,, get ridgeless btw


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