Rebuild Kits or Source For Ulka EP5 Pump Parts?

Equipment doesn't work? Troubleshooting? If you're handy, members can help.
dracon
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Joined: 14 years ago

#1: Post by dracon »

I need either a rebuild kit or a source of specific pump parts for the Ulka EP5. Or...even someone who recycles the Ulka EP5 parts. A great web-page detailing the internal pump parts is at:
http://ulkapumprepair.blogspot.com/2008 ... -page.html
The piston that I need is the silver cylinder-ish part between the two large springs in the top half of this picture:
http://www.myschiffman.org/cg/pump_parts.jpg

I've been unable to find such a source. The Ulka EP5 seems to be VERY common in espresso machines and I'm actually surprised a re-build kit isn't readily available. In my case all I need is a replacement piston and it's ludicrous for people to have to spend US$50-60+ for the whole pump and basically throw-away otherwise perfectly good parts.

All I've found for sale are complete assembled pumps at higher than necessary prices and usually with excessive shipping prices. (e.g. I know the Ulka EP5 could be mailed for about US$4 using 1st Class Mail. I buy similar size and weight electronic components shipped like that all the time)

In my case simple dis-assembly and cleaning did not help much. Everything in the Ulka EP5 pump is in GREAT shape...except for the piston. The piston is very badly corroded due to being constantly immersed in water (plus the design puts dissimilar metals in contact with each other in water). I think the rust-promoting design is common to most of the machines out there.

A re-build kit (e.g. for a carburetor) generally contains many or all the replaceable internal parts of a mechanical item. In the case of the Ulka EP5 pump, a universal re-build kit would most likely contain the o-rings, the rubber bob on the spring, the nylon ball, the springs, and the piston. Those are the parts most likely to wear out, become deformed, rust, deteriorate, etc.

Re-build kits are almost always cheaper than buying the complete manufactured item (even at refurbished prices), or if they aren't cheaper they are usually made with better parts (design or materials). They're usually also easier and cheaper to ship and have less impact on the environment.

Example of a rebuild kit for a "steam valve" on another espresso machine
http://www.precisiontamp.com/product/MZ ... L165K.html


edit to add:
My Krups XP2010 is a bit under 3 years old and has been used almost every day to make 1 to 3 servings.
Note: the Krups XP2010 came with a 1 year limited warranty, but from the user manual "The limited warranty does not cover coffee makers that fail or work poorly due to scale."

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lsjms
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#2: Post by lsjms »

It is a sting, I found it cheaper to buy a second hand Krups (or delongi etc) at £10. Rip the pump out.
LMWDP #277

dracon (original poster)
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Joined: 14 years ago

#3: Post by dracon (original poster) »

I understand your suggestion, but from what I've been reading it seems the water pump is the highest failing part in these machines. I'm concerned the likely reason someone would want to try to sell their machine is because it's broken.

You do however give me an idea for another question I'm going to ask on the forum. It may help others as well.

I just can't help thinking that with the tens of millions of espresso machines out there using this pump that someone (including the manufacturers) hasn't started a side-business of recycling the pumps (or even entire machines) and as the used car parts people say, "parting" them out. Seems like an opportunity :idea: . Maybe they just figure the typical espresso machine owner is just so loaded with cash he/she will always simply buy an entire replacement machine?

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civ
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#4: Post by civ »

Hello:
dracon wrote: I need either a rebuild kit or a source of specific pump parts for the Ulka EP5. Or... even someone who recycles the Ulka EP5 parts.
As far as I know there's no such thing.
If a pump is shot beyond repair (usually a blasted coil or missing / lost parts during disassembly) it's usually much cheaper to buy an old home brewer with a working pump.

But first ...
Are you sure that the problem is the piston and not anything else?
I'm not saying it isn't, but I have never read / heard of a corroded piston.

Ulka pumps like this one you refer to are relatively simple devices designed to work in constant contact with water while moving back and forth at 50/60 cycles per second and for as long as 2 minutes straight.
I understand that the materials they are made from are those the manufacturer found adequate for that specific function which would (I expect) exclude the possibility of corrosion in the conditions described above.

Now, if your pump has worked under other more severe conditions, ie: different liquids which would affect the (stainless steel?) piston's integrity eg: acids, that would be a different story altogether.


Close up of a piston from an Ulka pump
Photo by Rod Schiffman

From what I have seen / read, the most usual problems with Ulka pumps are a) overheating (blasted coil) which can be avoided with the use of a klixon or b) scaling, which can be solved with a thorough cleaning in white vinegar or citric acid.

Check this site for some very good info on Ulka pump repair:

http://ulkapumprepair.blogspot.com/

Hope you get the problem solved.

Cheers,

CIV

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lsjms
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#5: Post by lsjms »

The pump I replaced was a vibropompecity, hard to estimate but I guess it had seen a good 15 years action.When stripped and descaled the piston (s.steel) was in perfect nick, but the pump would not make pressure.
The vibe pump is inherently reliable due to simplicity, when a machine dies (especially a sub$100 one) it is hard for people to to outlay for what seems like expensive parts, bear in mind some folk have machines costing £x000 that still have a vibe pump.
LMWDP #277

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HB
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#6: Post by HB »

lsjms wrote:...I guess it had seen a good 15 years action.
15 years! :shock: The owner got good value out of that pump!

Back to your original question, it's less expensive to replace a "field replaceable unit" like a vibratory pump than pay a technician prevailing shop rates to disassemble/repair/reinstall it. Even if you could source repair kits, I know some vendors are reluctant to sell such parts since they may generate costly follow-up inquiries from owners attempting repairs on the cheap. I understand that's no comfort to DIY repairers who consider their time "free".
Dan Kehn

dracon (original poster)
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#7: Post by dracon (original poster) »

civ wrote: Are you sure that the problem is the piston and not anything else?
I'm not saying it isn't, but I have never read / heard of a corroded piston.
Yes, I'm sure. I've already disassembled, cleaned, and reassembled the pump. The piston is SEVERELY corroded. When I took it apart, there was rust as well. Most current consumer-grade "stainless steel" is not rust-proof. When constantly immersed in water, especially when two dissimilar metals (e.g. a spring and the piston) are in contact with each other (which initiates galvanic corrosion), "stainless steel" will still rust/corrode in clean water. And the piston in the Ulka EP5 since it must by design be significantly attracted to the varying magnetic fields in the pump, must be a fairly high iron content steel. That reduces its resistance to rusting/corroding. In most water-pump based espresso machine designs I've seen, the pump is always filled with water...even when it is not in use...unless the user runs it dry (and even then a tiny bit of water still remains in the pump).

And, running it dry can quickly damage the pump. As there is no water to cool the assembly, it fails by overheating and can also cause a "blasted coil" as you said. A thermal circuit breaker mounted on the Ulka pump casing is supposed to help prevent that. There is a built-in mounting point for a thermal breaker. But, because it is on the exterior of the plastic casing (which provides poor thermal coupling) the thermal breaker isn't always effective. Also, some espresso machines may not even include a thermal breaker in order to reduce their manufacturing cost. As I recall, the temperature limit of the thermal circuit breaker mounted on the Ulka EP5 in my Krups XP2010 is 250degF, but I'm not sure I'm remembering that correctly. I just glanced at it as I was re-assembling the machine.

dracon (original poster)
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#8: Post by dracon (original poster) »

lsjms wrote: ...bear in mind some folk have machines costing £x000 that still have a vibe pump.
Yeah...as best I can tell from online resources, the US$1300 (retail) Bugatti 15DIVAC3110 Diva espresso machine may use the same pump.

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espressme
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#9: Post by espressme »

After refurbing a few machines, my take on these pumps is that..The pump is worth replacing! I find that some pumps will be fine after refurb and cleaning but on many the mushroom valve develops a leak or has worn so badly that the pump no longer works. The pump replacement as a matter of course can save headaches on recalls. There is another thread that speaks of a pump losing suction which requires filling of the intake line with a syringe or turkey baster.
-Richard
richard penney LMWDP #090,

dracon (original poster)
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#10: Post by dracon (original poster) »

@espressme

I noticed that the Ulka EP5's "mushroom valve"
(item #4 in the http://www.myschiffman.org/cg/pump_parts.jpg image I referenced in my original post)
was slightly deformed and swollen compared to the crisp edges in the reference image. I suspect that over time as it continues to be constantly immersed in water, the rubber "mushroom" part of the valve will deteriorate and eventually contribute to pumping problems. For now, the valve's action is still smooth and there is no binding. I think the deterioration will be similar to the way rubber components in toilet tanks swell and deteriorate due to their constant immersion in water.

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