Problems with portafilter fit of La Marzocco GS3 MP

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rnshaw
Posts: 38
Joined: 9 years ago

#1: Post by rnshaw »

I just acquired a barely used GS3 MP, and I must say, I am ecstatic! After the second shot I was matching anything I get from great coffee shops. Amazing!

The portafilter only tightens to about the 7 o'clock position, which is not very far. Indeed, under pressure, it tends to back out. It was replaced in April with an OEM gasket from Espressoparts. Could it be the gasket is an aftermarket gasket and too thick? Perhaps the gasket is upside down? Could other O-rings be causing this?

Thanks

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uscfroadie
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#2: Post by uscfroadie »

The 7 o'clock position is normal. Usually if I see leaking it's due to grounds on the gasket. Scrub it with a brush and see if the leak disappears.

When you need replacements I highly recommend the silicone gaskets from Cafelat.
Merle

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LukeFlynn
Posts: 1293
Joined: 10 years ago

#3: Post by LukeFlynn »

rnshaw wrote:I just acquired a barely used GS3 MP, and I must say, I am ecstatic! After the second shot I was matching anything I get from great coffee shops. Amazing!

The portafilter only tightens to about the 7 o'clock position, which is not very far. Indeed, under pressure, it tends to back out. It was replaced in April with an OEM gasket from Espressoparts. Could it be the gasket is an aftermarket gasket and too thick? Perhaps the gasket is upside down? Could other O-rings be causing this?

Thanks
If LM still use the thick conical gaskets with a lip on them.. the lip needs to be facing downwards, otherwise your portafilter will start to come out of the group as pressure builds.. like you describe.. that said the PF will still sit at 7 o'clock until the gasket gets substantially worn. (Just try flipping it around in case it's upside down) I agree with Merle though, silicone gaskets are magnificent.

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keno
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#4: Post by keno »

There are two available conical LM gaskets which are used in most of their machines.

The 6/8mm gasket is for newer machines with minimal wear of the portafilter and group. When new the portafilter will sit at 7 o'clock until the gasket compresses or the parts wear.

The 7/9mm gasket is for older machines with more wear so that the portafilter doesn't go all the way over to 4 or 5 o'clock.

It's possible you have the latter, but doubtful if as you say the machine has been hardly used since its normal for the handle to sit at 7 o'clock in a new machine. As was mentioned above make sure the gasket was installed correctly and if so just torque it a little harder and it should not back out during a shot.

rnshaw (original poster)
Posts: 38
Joined: 9 years ago

#5: Post by rnshaw (original poster) »

Thanks, everyone! Now if I can just keep making great coffee consistently.

Uldall
Posts: 110
Joined: 10 years ago

#6: Post by Uldall »

With those 2 machines you Can make the Best espresso.
The rest is up too the barista :-)
Remember fresh beens.

/Uldall
Bassethound.
Coffee Driven.

suprolla
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#7: Post by suprolla »

Just chiming in with my own experience. I was accustomed to my Cremina portafilter which did not takeuch effort to lock down. I then purchased a "Cremina with a pump" machine and was using the same technique. I had sealing issues and did not know any better. As far as I was aware at the time, I was locking down the portafilter.

Guess what, I was not really locking it down. This machine needed a lot more force to lock down the portafilter than the other, and now I have no issues with it. Same gasket sizes, same portafilter, but at least twice the force for it to lock without leaking.
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