I've got an Astoria Argenta SAE 2 HX automatic.
On the right group, as it starts to choke (either with a too fine grind or when I'm back-flushing) the buzzing goes from a slight vibration to the sound of an old analogue oven timer. A tinny, mechanical sounding buzz.
I've removed the front panel, and it sound as if it's coming from above the group, so it's most likely not in the three way solenoid, nucleus area, and the side panel where the pump lives, and the pump and motor seem to be quiet when this happens.
The left group is quiet and happy, sounds normal.
Does this sound familiar to anyone, before I start randomly taking things apart to see which part stops the noise?

Bubble compressing in the group? If it is plumbed, crack the group bolt and let the water bleed out then tighten it back up and see what happens.

USE A LONG, large slotted screwdriver (like a Craftsman with a knob-end handle. The knob goes in the ear (no wise cracks!), and use it like a stethoscope, probing with the tip to locate the source of the sound. If it was a vibratory pump machine I would guess a loose or weak valve pulsating in rhythm with the pulsations of the pump's output. If one vane of the pump is a little weak, and a bypass, one-way, or 3-way valve was also a bit weak, it could account for the sound.

You could get technical and record it, play it back in slow speed or view the wave form to see if it is in synch with the 60 cycle AC. If nothing else, it would impress the heck out of the next tech who has to service it when you tell the tech the story!

Sue a log?


Oh, "Use a long..."


HAHAH, one of the ads for this thread that came up was:

Large Sound Piezo Buzzer 110dB/1m (@6VDC) Large Sound Buzzer Bimorph Actuator, 2mm Piezo Buzzer

Maybe that's your problem....

If it is a 60hz hum, like Randy suggests it might, I'd suspect the coil for the solenoid maybe vibrating against something...you might try touching the solenoid and seeing if the buzz goes away or if you feel it. Maybe it's as simple as tightening the coil onto the valve body.

allon wrote:Sue a log?.

I'm a pretty good writer.. I am a LOUSY proof reader...

Randy G. wrote:use it like a stethoscope

Or I could use my stethoscope. I put enough dirty tools in my ears wrenching scoots over the years that I just got one...

Randy G. wrote: a vibratory pump machine

Nah, rotary pump...

Randy G. wrote:If one vane of the pump is a little weak,

...it would make the same sound regardless of group used, n'est ce pas?

Randy G. wrote:and a bypass, one-way, or 3-way valve was also a bit weak,

Bypass would engage with either group, and it's not the three way valve at the bottom of the right group, but one-way valve? Elaborate, please! Where in the hydraulic chain does this occur? What does it do? Are there one of these for each group? Or could the fact that it's happening on one and not the other rule this out as well?

allon wrote:you might try touching the solenoid and seeing if the buzz goes away or if you feel it. Maybe it's as simple as tightening the coil onto the valve body.

"It's *NOD* a tooo-muh!" ; >

Seriously, with my head right at the solenoid for the three-way valve, I can hear the noise coming from above the group. I am 98.994% sure that it isn't the solenoid or the three way valve.

If there aren't anyone that says "Oh, I know that! That's yer (fill in the blank)!", of course, I'm swapping the brand new nucleus to the noisy group to see if the noise goes with the old nucleus and bits, and continuing to swap parts till the noise crosses the center-line, assuming at that point that the problem lies with the last part moved.

Thanks fer playing, though, ever-buddy! I appreciate the input. Any diagnostics that I can do on the interweb saves me standing over a hot, wet machine in my kitchen, where it's already in the nineties and humid already...