Rotary Pump HX Espresso Machines & Their Sounds - Page 2

http://users.rcn.com/erics/ · by **erics** on Mon Apr 28, 2008 11:58 pm

Another thing to think about, although it might take a little bit of work, would be to TEMPORARILY mount and run the new pump/motor outside of the machine initially. If you need a copy of the Bunn manual (pdf), email me at erics@erols.com

If your machine is as described in the manual, it has hard piping (copper tubing) connected to both the inlet and outlet of the pump and, personally, that would be one of the first changes I would make in addition to soft mounting the motor unit.

by **mhoy** on Tue Apr 29, 2008 12:02 am

Erics: What does one use for a soft mount instead of copper?

http://users.rcn.com/erics/ · by **erics** on Tue Apr 29, 2008 5:21 am

For David's Bunn ES-1A, I was "working" with what I saw in the operation/service manual. It indicates copper tubing vice teflon or SS braid over teflon for the connections to/from the pump. Actually, his machine is technically correct in that the motor/pump appears to be hard mounted and the connections are "hard". If a motor/pump were soft-mounted, one would typically NOT have hard connections between the pump and machine components.

Doing a search on the McMaster-Carr website for "sound isolation mounts", there is a myriad of choices for the pump/motor unit. As far as connections between a soft-mounted pump and a machine, a flex connection, transitioning to metallic tubing would seem appropriate.

by **LeoZ** on Tue Apr 29, 2008 2:35 pm

HB wrote:Vibratory pumps get a bad rap because... they vibrate. If you run one free from an espresso machine's casing, it makes less noise than an electric razor. Alas vibratory pumps do indeed vibrate, producing a tinny reverberation of interior components. I'm not making this up, I "outboarded" mine and the noise level is about the same as an inboard rotary pump:

how outboard is outboard? i dont know the specs of vibratory pumps, but id be nervous to run out of head with even a couple feet of extra hose on it.. you notice anything loss of pressure with the setup?

by HB on Tue Apr 29, 2008 9:09 pm

The pump is directly beneath the machine in the cabinet below. In years of use, I've never had a problem (*). I believe vibratory pumps are technically spec'd at zero inlet pressure and mine is supplied 20 PSI, so I'm already off the reservation. It seemed worth the risk.

(*) Oh great, my saying that assures the pump will fail the very next time I use it.

by **markr** on Tue Apr 29, 2008 9:11 pm

LeoZ wrote:how outboard is outboard? i dont know the specs of vibratory pumps, but id be nervous to run out of head with even a couple feet of extra hose on it.. you notice anything loss of pressure with the setup?

I outboarded the vibe pump on my Brewtus last night. I'm running it through 1.5m of braided hose similar to that shown in HB's photo with the pump on the floor beneath the machine, so a vertical lift of around 0.9m. Pressure at the brewhead was identical to that measured before the outboarding. I have no idea if this is straining the pump or not, but I see this as a step towards replacing the vibe with a rotary and plumbing in fully anyway, so I'm not too concerned if it dies earlier as a result.

by **dmankin** on Tue Apr 29, 2008 9:35 pm

Well, I successfully removed my pump today. Here's a photo of it, where you can clearly see where the adjustment screw snapped off, as well as the obvious leak location.

Tomorrow, I'll try to run the motor alone to see how noisy it is without the pump attached.

David

http://users.rcn.com/erics/ · by **erics** on Tue Apr 29, 2008 10:11 pm

David -

See this: http://www.depcopump.com/datashee...rotary%20parts.pdf

I'm thinking that Fluid-O-Tech and/or their distributors have rebuilt units in stock in the event you do not have sources.

by **dmankin** on Wed Apr 30, 2008 10:07 am

Thanks, Eric. I plan to send the pump to J C Beverage in Minnesota for a complete rebuild. They charge $43.50, which seems more than reasonable to me. The rebuilding of the pump will fix my leaking pump problem, but there is still the issue of sound to address.

Check out this video of my motor running without the pump attached - by no means silent, or even close! Is this abnormal? Acceptable? Can one lubricate a noisy motor? I can rest just fine with the machine's noise level, but I really want to figure if this machine is meant to be this loud, or did it come from the factory nearly silent and has worked its way to this point.

Thanks for all your input.
David

http://users.rcn.com/erics/ · by **erics** on Wed Apr 30, 2008 10:46 am

Good choice on the pump rebuild - I had read about them in another post - maybe CG - and was trying to hunt them down for ya but . . .

I can't comment on the motor noise other than to say it does not sound like a motor bearing problem but, at the same time, DOES NOT sound normal. I would liken it to a transformer (coil) hum or whine.

Maybe a new post (with different subject heading) with this same video would attract an electric motor guru.

I see that the motor is soft mounted - good - but was there any flexible piping between the pump and the machine?


Contact Us	Legal disclaimer and copyright: This content and all its parts are copyrighted, all rights reserved. Content including all text and images in part or in whole may not be reproduced in any electronic or printed medium without prior permission. Home-Barista, Home-Barista.com and related logos are trademarks of Home-Barista.com, LLC. Other trademarks are the property of their respective owners. By accessing this site, you agree to the terms of service. Overall speed: , current page: s, avg: s, max: s