Replacing La Marzocco GS3 vacuum breaker - Page 2

Equipment doesn't work? Troubleshooting? If you're handy, members can help.
DaveC

#11: Post by DaveC »

DaumierS wrote:Actually, the thread of the new vacuum breaker is of a smaller diameter, so you have to use the new fitting elbow
That's a pity...

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Peppersass
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#12: Post by Peppersass »

DaumierS wrote:I am looking at it, and it shows the old vacuum breaker:
https://drive.google.com/file/d/15jmw0o ... sp=sharing
The new memory metal vacuum breaker is the one all the way to the right. It doesn't show the beginning serial number, so I'm wondering if it's not a stock production part and is only available as an upgrade.

The middle one is from GS/3 serial numbers 636-1169, which were made roughly in the 2008-2011 time frame (not sure about the ending date.) Before that, they used parts 10, 17 and 18, but not the unnumbered silicone cap shown in the drawing. Both versions vented directly inside the machine, which was a disaster waiting to happen. Condensed steam and sputtering water would accumulate inside the machine and find its way to the logic board in the brain box under the steam boiler, usually causing shorts on the board that produced anything from weird symptoms to a dead machine. I believe the silicone cap, which sort of sealed against the top of the rear panel, was supposed to contain the steam, but it didn't.

The one on the far left was the production model after serial number 1169. A silicone tube is attached to the spout. The other end is connected to a new fitting in the rail above the drain box, allowing steam and water to drain into the box. For people with older models that don't have the new drain box fitting, LM provides a T-fitting that allows the new tube to share the drain box fitting used for the OPV. Venting the breaker into the drain box solves the logic board contamination problem. The new memory metal version also vents into the drain box through a silicone tube

My machine, which is serial number 613, came with the silicone cap. My guess is that when LM decided to add it for production models, they sent silicone caps out to distributors and dealers to install on older machines in their inventories or on their repair benches.

DaumierS (original poster)

#13: Post by DaumierS (original poster) »

Peppersass wrote:The new memory metal vacuum breaker is the one all the way to the right. It doesn't show the beginning serial number, so I'm wondering if it's not a stock production part and is only available as an upgrade.
Yes, there are three vacuum breakers. The one on the left (old), the one on the right (newest). But I was sold the third one:
https://home.lamarzoccousa.com/product/ ... m-breaker/
This thirds one LM identifies as a Linear Mini breaker. The dealer I purchased it from (not LM USA) listed it as a GS3 part. And indeed, it does not fit GS3.

Still looking forward to receiving the new one from LM.

Thank you very much! Your comments, as usual, are very detailed and helpful. I am learning a lot from you.

I only wonder, why LM does not have videos for all basic maintenance tasks, for replacing all the valves, for testing, etc. This would certainly help their sales... May be this is a liability problem for them....

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Peppersass
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#14: Post by Peppersass »

I don't think it's a matter of LM wanting to avoid liability. They provide detailed written instructions for installation, technical bulletins with important maintenance information, and guidelines for when to perform various maintenance tasks (though not necessarily how to do them.) They also provide detailed instructions for maintaining the group and conical valves in GS/3 MPs, as well as detailed instructions for retrofitting older GS/3 MPs with the conical valve.

My sense is that LM's approach has been defined by the long history of their machines being used in commercial environments, where maintenance is usually performed by factory-authorized technicians who have been trained by LM and know what they're doing, and the machines are maintained by them on a regular schedule, as opposed to only when needed. Also, I'm sure LM's preference for the home market is that all maintenance be done by factory authorized technicians, dealers, etc., not necessarily for liability protection but to avoid mishaps that end up costing them dollars and reputation. Their support for DIY home users hasn't caught up.

I know of one LM maintenance video: how to maintain the group head valve in a GS/3 MP. Unfortunately, it's the old version of the valve, not the newer conical version. I think they had to do this because the old valve required maintenance every 6 months or so.

Note that Chris Coffee has posted articles and a few videos showing how to do various maintenance and kit installation tasks. They used to have one on replacing the gicleur, but it's not posted anymore.

There are also many posts here on HB with instructions and photos of maintenance and repair tasks for the GS/3. Here's one on servicing the "left-most" vacuum breaker shown in the parts catalog, which is presumably the one you want.

Splunge
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#15: Post by Splunge »

Peppersass wrote: Unfortunately, it's the old version of the valve, not the newer conical version. I think they had to do this because the old valve required maintenance every 6 months or so.
The newer GS3 group is apparently identical to the group on the Strada MP. I was sent the following link from the service department at IDC: http://www.youtube.com/watch?v=Tj4-EdKS8js
Chris

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Jake_G
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#16: Post by Jake_G »

Splunge wrote:The newer GS3 group is apparently identical to the group on the Strada MP.
While this is true, that is a video for the old helix style MP, and not the newer conical valve.
LMWDP #704

Splunge
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#17: Post by Splunge »

Dang! Apologies.
I saw the group gauge on top and assumed it was the new MP.
Guess I'll be on my own with this one - but thinking now they've probably sent me the wrong obscenely-expensive o-ring kit.
Will check that before I tear things apart.

edited to correct horrible spelling
Chris

cebseb

#18: Post by cebseb »

@Splunge did you pay for the O-ring kit? I'm guessing you still have the old style MP valve then? More often than not, you just need those three small o-rings to replace on the valve and not the rest of the parts that come along in the kit. I usually just purchase a silicone o-ring kit that holds several different diameters of o-rings. It has been helpful in maintaining all sorts of different machines including my Mistral.

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Peppersass
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#19: Post by Peppersass »

DaumierS wrote:If it is not too much to ask, can you provide links for the kit and for the O-ring? Thank you!
You have to call LM USA to order them.

Splunge
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#20: Post by Splunge »

cebseb wrote:@Splunge did you pay for the O-ring kit? I'm guessing you still have the old style MP valve then?
Yes. My group is the new one (machine built mid 2020), but guessing they sold me the kit for the old one. Emailed them last night after business hours so don't expect to hear back till Tues. In the meantime I'll compare part numbers on my bags to those on the exploded diagrams of the old and new groups to confirm - it'll be fun! :?

A few months ago my group developed a very slow drip, once every 30 seconds or so. Assuming it'd only get worse I ordered the kit just to have it on hand so I wouldn't have to resort to my backup Silvia for an extended period. In the meantime it's gotten much better, maybe one drip a minute. As I don't think o-rings can heal themselves, I'm guessing there must've been a chunk of something in there that's now shifted maybe. Either way, I like to have spare parts on hand - just need to make sure they're the right ones!
Chris