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.