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Pasquini Livietta and low flow issue

Postby Cafedenda on Sun Nov 27, 2011 6:40 pm

I finally found some time to look at the Livietta ('87/54mm group) that I acquired recently. I have gone through many posts and I think I know what the issue is but would like to ask the group anyway. Initially, the pump (looks identical to other posters' Fluid-O-Tech pump) made a very low noise with little vibration. I opened up to connections right after the pump and found that the flow restrictor (shown in RAS' post here) has scaled up almost completely. I removed the scale but there was still no water. I took the fittings apart again and found 2 small irregular shaped pellets (one is dark stone color, the other one is white) that was clogging the outlet. The pump seemed to be working but with irregular water flow. Per RAS' post, it looks like I need to open up the pump to make sure that some of the rubber gaskets and such are still in good shape. It could be that the previous owner allowed the pump to just run and run when they couldn't get much water out of the group head and ruined something inside.

I found this label that fell off inside the machine but I am not sure where it came from as I don't recognize the brand. If it's the brand of the pump, does this mean that the pump has a max flow rate of 6 bars?
Image

Here's my sequence to testing the flow rate, though I didn't have to let the machine heat up:
1. Turn on machine and activate the brew switch to allow water to come out of the group
2. Allow machine to heat up for 15-20 minutes
3. Turn pump on for 30 seconds with nothing in the group head
4. Water flows normally for a few seconds and then within 5 or 6 seconds, it slows down to a few drops.
5. In another few seconds, the flow resumes again but at a reduced rate
6. At the end of this 30 seconds, I get about 180 ml

Later, in another sequence:
1. Turn on pump for about 5 seconds to where the flow starts to slow down
2. Turn off pump and wait for 30-60 seconds
3. Turn on pump for 30 seconds with nothing in the group head
4. Very little water for the first few seconds then reduced flow and I get about 125 ml

The weird thing is, the grind that I used is within a mark or two (Wega/Compak K10) of what I used for the 58mm VST basket and I get about 2 oz of espresso in 30 seconds with beautiful crema. The taste is noticeably lighter than my E61 machine but still very tasty. I am still using the plastic tamper so that could be it as well. Using a foam cup, the K-type thermocouple shows that the water temperature in the cup is about 190 deg F. The group head shows about 170-175 deg F at idle though I didn't use the appropriate tape to secure the leads. Looks like the previous owner knew what he was doing because the pstat is adjusted all the way down in its travel and the 3-way solenoid outlet to the drip tray is already turned 45 degrees inward to minimize splashing. Well, more info than needed but please give me your take on the pump. Thank you.
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Postby Jeff on Sun Nov 27, 2011 11:53 pm

I believe that label is from a solenoid valve. See page 6 (labeled 3) in http://www.berke-ltd.com/TBerke2009.pdf
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Postby Cafedenda on Mon Nov 28, 2011 9:34 pm

That's the one. Thanks for the link as it lessens one of my confusion. I was thinking that the pump was designed to output 6 bars max. Hopefully, someone will chime in before I take the pump apart needlessly.
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Postby jarviscochrane on Tue Nov 29, 2011 7:48 pm

You may want to check the HX for scale which may be causing the irregular flow rates. I wouldnt hesitate to take apart the pump either. There is a small spring in there that has small plastic or rubber ends that open and close as the pump vibrates. The grey and white bits you describe may be these ends. I had similar behavior from a vibe pump and found the spring inside had rusted through. Max pressure was 6 bar against a blind basket with the broken spring.
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Postby Cafedenda on Tue Nov 29, 2011 10:07 pm

You are probably correct because I have already done the descale of both the boiler and the HX. Since this is a simple machine and I don't see water escaping into the boiler or out the 3-way valve, the pump is probably the culprit. Thanks for bringing up the broken bits. I do remember that after I removed the flow restrictor and found the bits, the water at seemed particular milky. I'll need to open up the pump soon.
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Postby jonny on Wed Nov 30, 2011 12:37 am

I have completely taken apart the FOT pump and documented with photos, so if you need any help, let me know. If you need it and you ask nicely, maybe I'll make a thread for it :wink:
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Postby Cafedenda on Wed Nov 30, 2011 2:02 am

jonny, I will certainly seek your help, if needed. Thank you for offering. I probably won't get to opening up the pump til later this week. Btw, I enjoyed reading the adventure that you went through with your unit. It was a huge undertaking and I am glad your shared it with us.
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Postby RAS on Wed Nov 30, 2011 5:45 pm

Hello Tiep,

Sorry I'm late to the party here... have you isolated your machine's flow issues to the pump? Based on the machines many of us have restored, it just sounds like replacing the original should be a first-step in the restoration. Did it for me, and the machine continues to impress me. Obviously, it's also important to look for blocks in both the feed and exit lines for the pump.
Bob
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Postby Cafedenda on Wed Nov 30, 2011 8:03 pm

Hey Bob, no, I haven't had time to dive into this machine yet. I will do so this weekend. I read about your o ring or pump gasket issue and will try to not mess it up. I am curious, did you attempt to get parts to fix yours at all? Looked like you just gave up and bought a new pump. Btw, I sent you a PM regarding availability of the insulator. I am actually not sure if I need it with this machine as it warms up pretty quickly, probably within 20 minutes of starting up. I usually just make a few doubles and then the machine is off til the next morning. Always fun to accessorize it though.
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Postby RAS on Thu Dec 01, 2011 9:13 pm

Yes, I looked for parts, but could find none for my 21 year old pump. Too bad too because every other aspect of it was perfect, and it has cool cast brass pieces that I just like :wink: .

Yeah, I got your PM, but when I tried to open it, I got a message saying that it had been deleted or retracted. No worries - please try again, a I'll get you set up with some insulation. What I believe the benefit of the insulation is that with more heat being retained in the actual boiler, the heating element needs to cycle less often and will therefore use less electricity, and should theoretically last longer. Also, I like the water in the reservoir just doesn't get as hot.
Bob
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