Lambro - weak flow - Page 2

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#11: Post by espressotime »

Do you have a picture of your group from the side?

Paolo (original poster)

#12: Post by Paolo (original poster) »

With the acorn cap removed-

Paolo (original poster)

#13: Post by Paolo (original poster) »

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#14: Post by espressotime »

I mean the entire group with the nut of the regularor installed.
Like this:

The part with the red line measures 56 mm on mine.

Also the nut on my regularor is rounded .

Looks as if you got te older style shut off valve. I don' t think it can really be adjusted.It is an on-off system.

To me it doesn't matter I can't control the flow perfectly on my group.
It still makes great espresso.
If the spring below the ball bearing would be replaced by a stronger one I think flow adjustment would be better.

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#15: Post by vberch »

I didn't realize it was a different group. I thought it was the same Zodiaco group as what Dominick and I have, but with a different style end cap on the flow control valve.
espressotime wrote:That's a different group.

Paolo (original poster)

#16: Post by Paolo (original poster) »

Hi Alf,
As far as I know, my Lambro was made between 1960 and 1962.

The part that measured 56mm on your Lambro is 76mm on my machine.

The nut covering the threaded bolt at the bottom of the back of the group is not shaped like the one on your machine.

I haven't used my Lambro much for a few weeks and its behaviour is now different to what it was before.
The weird thing is that I was able to adjust the flow for the first couple of years of ownership. I had set it to the flow that I wanted and left it. It is only now that I feel that the pre-infusion flow is less than ideal that I realise that it is no longer adjustable.

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#17: Post by espressotime »

Ok then.I guess you have a " normal" Lambro.The nut at the bottom on your Lambro is pointed.Mine is round.As far as I know you should be able to control the flow on your machine.
I' ve been using mine for only 6 months now so probably you're more of an expert than I am.Maybe on of the springs is broken?

Paolo (original poster)

#18: Post by Paolo (original poster) »

vberch wrote:Here is a great post from Dominick showing how a Zodiaco group flow control valve should work: /levers/fae ... ml#p418034. Mine works in the same way. I adjusted mine for 270g per 30 secs flowrate. I know Dominick has a two group President and he adjusted one of his groups for slower and the other group for faster flowrate.
I just checked my Lambro....150gm of water in 30 seconds.

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#19: Post by vberch » replying to Paolo »

Paolo, it's not necessarily bad. Slayer recommends 40 to 60g per 30 secs: It all depends on the types of shots you are pulling. That being said, you obviously still should be able to fix the flow valve. It's fairly simple design. Majority of parts are available from Espresso Parts: ... ever-group.

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#20: Post by Jake_G »

Paolo wrote:I just checked my Lambro....150gm of water in 30 seconds.
Seems like you have a blockage somewhere between the boiler and the piston sleeve. Given the open HX design of the Lambro feeding the group with two thermosyphon pipes, the most likely scenario would be scale build up somewhere in the group between the group flange and the piston sleeve.

It is hard to say if the blockage (most likely limescale) is on the boiler side of your adjustment rod or the group side, but a simple test of warming up the machine with the rod removed would tell you. If you get copious amounts of water flowing from where the rod should be, then the blockage is downstream, towards the piston sleeve. If only 150gm of water flows out in 30s, then the blockage is upstream, between the rod and the flange where the thermosyphon tubes connect to the group.

If the issue is between the rod and the group, there are some localized descaling approaches you can take to remedy the issue. If it is further back in the group, you're probably best off to remove the group and descale it or just go ahead and put some citric acid or vinegar in the boiler and run it through the group. I hate to do that, but it will dissolve the limescale and fix the issue.


- Jake
LMWDP #704