Raising rotary pump pressure - Page 2

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Postby erics » Aug 12, 2018, 5:57 pm

If it takes 4-6 seconds for the water to exit the brew group with an empty or no portafilter, something is still amiss. A rebuilt pump may be in your future.

The valve you damaged can be sourced from Fluid-o-Tech or one of their distributors. Just be sure to have your complete pump nomenclature handy.

Eric S.
E-mail: erics at erols dot com

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Postby kolu » Aug 13, 2018, 3:33 am

and just for the future - you should lubricate only the O-Ring. everything else (especially the valve) should be kept as clean as possible.


Postby Leendert » Aug 13, 2018, 12:45 pm

Thanks Eric and Lucas,
Without this feedback I lack the confidence to open and modify the rotary pump.
I will look for a new bypass valve (№ 13). As I am not sure where to buy one (could be avola-coffeesystems.de, but I prefer an address in The Netherlands) and as I will be abroad for a while this might take more than a month. At proper time I will report my progress. Leendert.


Postby Leendert » Sep 14, 2018, 4:36 pm

I thank everybody in helping my problem with the stubborn bypass valve (№ 13 in the previous diagram). I replaced this bypass valve by a new one (ordered from Germany) and everything seems to be fine: a decent 9-9.5 bar brew pressure, the water almost immediately leaves the E61 brew group (e.g. in a cold-flush), no leaking via the expansion valve drain, a silent machine and excellent coffee.
I must confess that I did not expect (nor understand) that replacing the bypass valve would do the job. OK, I wrote that "I damaged this valve a little bit", but looking to the original bypass valve I just see minor ruptures in its shoulder (unfortunately this is hard to see on the previous photograph).
Anyhow, this exercise made me confident in overhauling the ECM. I am proficient enough to repair my bicycles (actually at high standards), but I was somewhat reluctant to open an almost virgin US$ 2,500 machine. Now, I got enthusiastic and opened, cleaned and lubricated the complete E61 brew head (finding none or hardly any scale in the brew head).
Thanks again. Met vriendelijke groet, Leendert van Staalduinen.


Postby stdo » Feb 23, 2019, 4:36 pm

Hi Leendert,

how did you get the bypass valve out of the pump?

And what to do to not destroy it?

Thanks in advance,