Repairing a ULKA vibratory pump

Need help with equipment usage or want to share your latest discovery?
DVL
Posts: 8
Joined: Fri Jan 20, 2006 3:17 am
Real Name: David
Equipment: La Pavoni piccolo, Nuova Simonelli Eli, Gaggia Baby, La Pavoni Pub, Inova I-1...
Location: Canada

Postby DVL » Fri Jan 20, 2006 3:37 am

First off, first time post here--but always lurking around CG or some espresso related site.

My problem today is...

ULKA pumps, how many wires. I just pulled apart a Gaggia Baby that I ebayed and noticed it had some backyard mechanics going on inside. Ugly connections, speaker wire spliced in, lose wires...not what I would call pretty. More what I would call a fire hazard. The one thing I noticed is that instead of the two blades for connections, like the other machines I have rooted through, this has one blade(ground?) and a connection with two wires coming off of it? Looks like a blade connection but doesn't pull off.

Any ideas? Please steer me in the right direction.

David

User avatar
Jerome a Nantes
Posts: 6
Joined: Tue Nov 15, 2005 2:13 pm
Real Name: Jerome
Equipment: Rancilio Silvia Mazzer Super Jolly Auto, La Pavoni Professionnal
Location: Nantes, France

Postby Jerome a Nantes » Fri Jan 20, 2006 11:14 am

Perhaps you'll find some help from an article about the ulka pump on my site :
http://www.madeinthegarage.com/articles.php?lng=fr&pg=36

There is two blades on ulka pump for connecting to the power (AC current : order is not important)
One wire pass thru the thermal fuse who have a logement in the ulka pump next to the two blades.

User avatar
HB
Posts: 14652
Joined: Fri Apr 29, 2005 9:13 pm
Real Name: Dan Kehn
Equipment: La Marzocco Strada, Elektra Microcasa a Leva, Compak K10 WBC
Location: Cary, NC

Postby HB » Fri Jan 20, 2006 11:26 am

Wow, the images alone make for an excellent internals tutorial on vibration pumps. Nice work Jerome! I hope you don't mind this direct link to show an example:

Image
Dan Kehn

User avatar
HB
Posts: 14652
Joined: Fri Apr 29, 2005 9:13 pm
Real Name: Dan Kehn
Equipment: La Marzocco Strada, Elektra Microcasa a Leva, Compak K10 WBC
Location: Cary, NC

Postby HB » Mon Jun 12, 2006 2:29 pm

Someone contacted me offline asking if it's possible to repair an espresso machine's vibe pump. It took awhile to relocate this very helpful how-to due to its obscure title: I ended up with a free Starbuck. I'll add this to the Resources page for future reference.

Below is another great schematic from Eric:

Image
From Pump? OPV? Check Valves? Wit's end!
Dan Kehn

User avatar
another_jim
Team HB
Posts: 9241
Joined: Thu May 05, 2005 1:16 am
Real Name: Jim Schulman
Location: Chicago

Postby another_jim » Fri Jan 05, 2007 4:51 pm

My thanks for these links and to their authors. My Semi OPV adventures earned me a small piece of grit in the little spring valve at the output end of the pump. These instructions allowed me to get the Semi back to its ridiculously overpressured lovely self in very short order.

BTW, the Ulka is a very well thought out gizmo; simply put together and easy to work on.

Droshi
Posts: 218
Joined: Tue Jul 01, 2008 7:13 am
Real Name: Andre
Equipment: Bezzera Strega, Mypressi Twist, OE Pharos, Old PeDe Handmill
Location: Houston, TX

Postby Droshi » Thu Feb 24, 2011 8:15 pm

Was just searching for this for a friend, sorry for the resurrection, but some topics are timeless!

Good links btw, thanks. :)

JimG
Posts: 663
Joined: Sun Jun 11, 2006 9:40 pm
Real Name: Jim Gallt
Equipment: Silvia+PID+groupsensor; Alexia+PID; Mazzer Mini E; Mazzer SJ w/electronic timer; Hottop+PID
Location: Lexington, KY

Postby JimG » Fri Feb 25, 2011 11:11 am

Great stuff! Thanks for resurrecting the thread.

Is there similar information available for the electrical side of these pumps? In particular, I would like to confirm/deny the rumored presence of rectifier diode(s) on the AC supply.

Jim

Little Tokyo - Coffee, Espresso, Teas, Chocolates
User avatar
Randy G.
Posts: 3305
Joined: Sat May 12, 2007 11:54 am
Real Name: Randy Glass
Equipment: Vibiemme Double Domo; Mazzer Kony, 3 Hottops, Espro Press, Hario, Clarity, etc.
Location: Yankee Hill, CA

Postby Randy G. » Fri Feb 25, 2011 11:50 am

JimG wrote: In particular, I would like to confirm/deny the rumored presence of rectifier diode(s) on the AC supply.

Just disconnect it and put an ohm meter across the feed wires to the pump, +/- and then -/+ and you can easily verify that.
Espresso! My Espresso!
http://www.EspressoMyEspresso.com

mini
Posts: 229
Joined: Sat Jul 18, 2009 1:05 am
Real Name: Matt McCurley
Equipment: Super Jolly, Le'lit PL041
Location: Atlanta, GA

Postby mini » Fri Feb 25, 2011 1:21 pm

Based on everything I have read, the pump uses simple half-wave rectification to pulse current into the solenoid. I haven't checked myself, but I would bet money there is a diode. It sounds like it's oscillating around 60Hz too.

Read through some of these links. I did a lot of research into Ulka pumps at one point, but I don't have the time to pull out specifics for you.
Repair of a Breville machine (w/ Ulka pump) including a schematic
CoffeeGeek thread on using voltage control
CoffeeSnobs thread with claims of rectifying diode

I don't know how the schematic in my first link was created, but FWIW, it does show a diode in line with the pump.
matt

User avatar
erics
Posts: 4651
Joined: Tue Aug 09, 2005 2:32 am
Real Name: Eric Svendson
Location: Silver Spring, MD

Postby erics » Fri Feb 25, 2011 2:13 pm

The rectifying diode is internal to the pump's coil wiring and is so indicated on the few Ulka housings (near the electrical connection terminals) I have seen.

And then of course, there is a thermal diode (typically called a Klixon or mfg by them) that is installed as an external add-on to lots of Ulka pump installations but not necessarily all.
Skål,

Eric S.
http://users.rcn.com/erics/
E-mail: erics at erols dot com