Changing gasket on La Marzocco GS/3

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espen
Posts: 1
Joined: 14 years ago

#1: Post by espen »

How often do you change the the gasket on a GS/3 and how do you do it? I run approx 76 shots each month.

In advance, thanks!

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HB
Admin
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Joined: 19 years ago

#2: Post by HB »

I would change the grouphead gasket when the portafilter no longer seals. Assuming the GS/3 is like other espresso machines, the grouphead gasket is friction-fit in a channel. Remove the dispersion screen as documented in the owner's manual and then tug the gasket out with the implement of your choosing (e.g., paint can opener, butter knife, bent paperclip).
Dan Kehn

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Peppersass
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#3: Post by Peppersass »

I make closer to 100 or more shots per month and have had the same gasket in my GS/3 since it was new back in the beginning of November, or about 7-1/2 months. There's no sign of leakage or cracks, and the rubber still feels supple. That said, if my gasket doesn't show any signs of wear by the 1-year mark I'll probably change it anyway.

What you want to watch for is hardening and/or cracking. Take a look at it with a flashlight, and poke it gently with a blunt instrument like the rounded end of a heavy paperclip. The gasket is made of very thick and dense rubber, so it won't give all that much even when new. But it should give a little. You can also get a sense of how supple the gasket is when you lock in the PF. You should feel a tad of give when you reach the fully locked position.

I think leaving the PF fully locked in the group when the machine is idle is bad for the gasket. I leave the PF very loosely engaged in the group, so there's as little contact between the basket rim and gasket as possible without the PF falling out.

Condition of the gasket could be affected by how long the machine is on continuously. I program my machine to turn off for about 8 hours a day. If you let it run all day, the gasket might wear out sooner.

The gasket is relatively easy to remove. As Dan says, remove the screw and shower screen. LM has provided two holes next to the gasket into which you can insert a bent tool. The short end of an allen wrench (hex key) works well. There's a hooked dental tool you can get at many drugstores that will work, or you can get one of the special tools sold by OrphanEspresso.com.

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haunce
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#4: Post by haunce »

Can you guys remember what way the GS/3 gasket is installed? Cone side towards portafilter or flat side towards portafilter? I can't remember :oops:

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Marshall
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#5: Post by Marshall replying to haunce »

I know H-B is DIY Central, and I don't want to rub it in (too much), but people who don't know which side of a portafilter gasket is up (the flat side) probably shouldn't be disassembling GS/3 paddle assemblies. The Pacific Northwest is loaded with LM technicians, and if you can afford a GS/3 you should be able to afford proper service for it. Just sayin'.
Marshall
Los Angeles

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haunce
Posts: 173
Joined: 12 years ago

#6: Post by haunce »

Thanks for your useful thoughts.

I popped out the gasket for the first time today and moved on to something else. When I returned to replace the new one, I forgot which orientation but installed it flat side up, which turns out is correct.

All I wanted was to double check. Couldn't find a picture online.

I already contacted LM USA for a technician and there is nobody within 300 miles of me. That is why I'm doing everything myself.