# Group head gasket seems stiff on Gaggia Classic



## Agentb (Feb 11, 2017)

Recently changed the gasket as the old one was starting to show some cracks, it was past its best shall we say.

With the old one, the PF handle would rotate around to about 5 o'clock ( looking from above) when loaded.

Now the new one, only travels round to about 7 o'clock and feels quite stiff. I've tried with a variety of baskets and two PFs i have - all the same.

Worse - if i try a finer grind and over tamp a little, the PF will start rotate off the group head just as the pressure builds, if i don't catch it - we have an espresso sauna and shower!









The new gasket is not a silicone one and is flat on both sides. The classic has the OPV down to 10 psi.

So a question for the Gaggia tifosi,

Is this going to get better over time, or have i bought a oversize gasket?


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## JojoS (Oct 1, 2014)

You probably used the 9mm.


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## L&R (Mar 8, 2018)

JojoS said:


> You probably used the 9mm.


This.


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## Agentb (Feb 11, 2017)

Thanks both - that would make sense

OK this was ordered,

Compatible Gaggia NG01/001 8,50mm rubber seal filter holder gasket Gaggia

but I can't say for certain what was delivered... I'm guessing 8.5mm the right size?


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## JojoS (Oct 1, 2014)

Best guess based on the info on the link is that it is for the stainless steel boiler types like post 2015 Gaggia Classic.


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## JojoS (Oct 1, 2014)

Try this https://www.amazon.co.uk/Gaggia-Rubber-Filter-Holder-NG01001/dp/B01H2T2HH0/ref=pd_sim_79_7?_encoding=UTF8&pd_rd_i=B01H2T2HH0&pd_rd_r=0aa7ce35-2ab4-11e9-b8be-5192fc4c5dd4&pd_rd_w=LW2UN&pd_rd_wg=nA9WI&pf_rd_p=1b8636ae-4f21-4403-a813-e8849dd46de4&pf_rd_r=Y41SJV04V0XYCPYHVBXN&psc=1&refRID=Y41SJV04V0XYCPYHVBXN


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## Agentb (Feb 11, 2017)

Thanks Jojo - i guess i'll have an emergency spare!


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## L&R (Mar 8, 2018)

Believe me or not I fixed several 9mm gaskets by sanding them down with a fine sand paper, this side went into the group head and the untouched side sealed the portafilter.

All machines work as they should and lock at 6 pm after the procedure.

BR


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## espressotechno (Apr 11, 2011)

The group seal should have the size (8.0, 8.5, 9) stamped on the inner face so you can decide which size new seal is appropriate .


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## Agentb (Feb 11, 2017)

Thanks L&R and espressotechno - every day is a Classic school-day.


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## ashcroc (Oct 28, 2016)

Agentb said:


> Thanks both - that would make sense
> 
> OK this was ordered,
> 
> ...


Looks like 8.5mm is right. I have the blue cafelat gasket in my tebe & it fits fine (depending on portafilter/basket configuration)

Laissez les bons temps rouler


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## Jumbo Ratty (Jan 12, 2015)

You have put it in the right way up haven't you ?

one side is flat, and the other side is rounded iirc


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## El carajillo (Mar 16, 2013)

On the web site other buyers have had the same problem ie too thick Take a look at reviews


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## Agentb (Feb 11, 2017)

OK decided to take a look, a really really close look... closer than the 10 seconds last time it left the plastic bag.









One face of the gasket does look ever so slightly rounded which was the side I had against the group head. I didn't notice that before...









That face also has D.V.M. at 6 oclock and 8 *5* at 12 oclock, no other writing anywhere (writing is about 1mm high and you won't see it unless you run your fingers over it.)

Not sure what DVM stands for but the size is 8.5 mm with crude measuring.

So nothing to lose and try the other way around.... and you guessed it, the PF is now at 6 oclock.









Thanks Jumbo for the pointer.









edit: DVM from here https://www.dvmengineering.net/


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## Jollybean (May 19, 2013)

I think rounded side up to the group head and flat side down to the portafilter is the normal way to install them. If it works fine the other way round though I would stick with it


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## Agentb (Feb 11, 2017)

By rounded i meant to say is almost impossible to see but you can feel the difference.

I've had a look at a couple of other black rubber gaskets on a couple of websites places which sell gaskets and had detailed photos which you could zoom in - the markings show GA and 8.5 so different from mine. I suspect they are genuine Gaggia ones, and i have a clone.

It's a bit hard to describe but the current way i have it in feels softer, and it feels just right - so i'm not pulling it out again!


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## Jollybean (May 19, 2013)

If it ain't broke - don't fix it


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