Over the past month, I've noticed an increasing incident of "sneezing" after I've pulled a shot and unlock the portafilter. It's nothing terribly dramatic - there's a faint noise, and there are some grinds on the portafilter, instead of remaining neatly in the basket, but I'm a bit puzzled as to why. Does the gasket need replacement? I can still backflush. It sounds to me that the "whoosh" that follows the end of a backflush / after stopping the shot is now more subdued / less powerful, but that could be imagined. Could the three way valve be clogged somehow?

Machine is cleaned and backflushed frequently with Cafiza; just disassembled and cleaned screen / gasket / mushroom a few months ago. Any ideas? Thanks in advance for your help!

bcquinn1 wrote:Could the three way valve be clogged somehow?

Judging from your cleaning regime, I doubt it's clogged. But the valve could be binding momentarily due to scale buildup.

Sorry to have been slow in responding, we just moved and we are finally starting to dig out : ).

So would you recommend backflushing with descaling solution? Just to be clear, I have a VBM Super Domobar Manual / Lever - the brew pump and valve are actuated by flipping a lever next to the grouphead.

Sorry, I misunderstood, thinking you referred to an E61 / solenoid combination. I don't see how the valves could fail to open when the lever is in the down position. From Purpose of the E61 middle brew lever position?:


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Rather than speculate further, I recommend removing the lower chamber to see what's up.

I had the same symptoms develop slowly on my Bricoletta. After a couple years got so there was virturally zero 3-way valve release action. Problem is/was caused by the lower pin that rides on the lever cam wearing down. Replaced pin 6 months or so ago all better. Ideally to reduce wear you need to pull the lever and lube the cam after every detergent backflush session. I'm not going there but instead will simply replace the lower pin every 2 or 3 years.

I agree with Mike and its relatively easy to check. With the machine cold and unplugged:

a. Put the brew lever in the brew position
b. Use a 1-7/16 open end wrench to remove the preinfusion AND drain chamber assembly as a unit from the grouphead.
c. The preinfusion valve assembly will simply lift right out.
It is part number F_223 shown here: http://www.espressoparts.com/cate...ma.e61manualgroup/

Inspect the top square pin for a groove worn into its surface from the cam. Excessive detergent backflushing can wash away lubricant films accumulated on the surfaces and aggravate this wear.

The total length of the assembly for the Vibiemme machines is 2.406 inches or ~61.1 mm. Note that Vibiemme groupheads are slightly different than the "standard" E-61 group and the part I referenced may/may not be the proper part. The Vibiemme expert close to you is this nice guy: http://espressocare.com/

Wow, thanks for all of your help. I will investigate and report back.

And, BTW, the dimension for the same part on Quickmill machines, pretty much a "standard" E-61 grouphead, is 2.073" or 52.65 mm. I just inspected mine (Quickmill Anita) and yes, the top pin shows some wear/polishing but definitely no visible groove. She is 2-1/3 years old and does 4 cappys a day.