How to salvage the wire connections of this ancient Ulka Pump (NH26)?

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samuellaw178
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#1: Post by samuellaw178 »

Long story short, I got an old La Cimbali Junior S/1 and it looked to be in decent condition. Only problem is the pump doesn't work.

So I tried to disassemble the Ulka Pump for checking the resistance/continuity. There're two red wires from the pump that go to the complicated wire nest(under drip tray), so I figure I don't want to mess there. The connection on the Ulka end looked like a spade connector so I tried pulling. Idiotically,turned out those are not spade connectors and I pulled out the wires which seem to be secured by some paste/glue. :oops:

Any idea if it's still salvageable at this stage? I can't seem to open into the solenoid.

Anyone has experience on this?





This is as far as I can reach so far


Thanks. :P

LukeFlynn
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#2: Post by LukeFlynn »

Vibratory pumps are dirt cheap, I would rather just pay $30-50 to get a brand new pump than mess with an ancient pump. I'd say others will agree with me, considering it's rare to do maintenance on a vibratory, they are just dirt cheap.

OldNuc
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#3: Post by OldNuc »

As the 1/4" F connector has burned off I would suspect the coil has at least partially shorted. New pump time has arrived.

samuellaw178 (original poster)
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#4: Post by samuellaw178 (original poster) replying to OldNuc »

Crap... :P

It's not about the cost, but the waiting time & my short patience. It's weekend today and Christmas is approaching. It'll be a week or more before I get the pump if I order now.

Also, another reason was this older pump seems more ruggardly built than the plasticky new version. I was hoping this one may be more quiet - usually the older stuff are built better.
Which is the 1/4" connector you refer to? :oops:

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cuppajoe
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#5: Post by cuppajoe »

When you checked the machine for operation, was there water in the tank? There should be a diving bell looking thing on a silicone hose that goes to the round grey device in the box under the drip tray. It detects water level and shuts the machine down when it gets below a certain level, which is adjustable.

The 'solenoid' is usually a sealed unit and would take some doing to get into. If you have little patience, working on this stuff may not be for you. I've been spending over three weeks just trying to replace a pipe on a Junior. And then there was the element on the SAMA Export... Murphy is part of the equation.
David - LMWDP 448

My coffee wasn't strong enough to defend itself - Tom Waits

D'Laine
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#6: Post by D'Laine »

The pump really looks like it is disposable.
If the two red wires went to the same electrical connection within the pump, you may be able to wire nut them together outside and shove one common wire into the 'hole'. How it's made secure mechanically is not apparent from the photos. It must be secure and not grounded.
There must be another wire to complete the high voltage circuit? Not shown.
If the ground is the 'other' conductor, then you've got a bit of a dangerous situation there.
Get a new pump that works on hot and neutral.

D.

samuellaw178 (original poster)
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#7: Post by samuellaw178 (original poster) »

Yup, there was water in the tank. Also, since the pump is not working for both boiler refill & brewing, I had to manually refill the boiler through one of the screw. Burnt element is the last thing I want, and good news is that is working.

I will source a new pump while working on this one then. Any ulka EP5/EX5 is fine right? What's the advantage of plastic/brass fitting? Can't find the information about this.

samuellaw178 (original poster)
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#8: Post by samuellaw178 (original poster) »

D'Laine wrote:If the two red wires went to the same electrical connection within the pump, you may be able to wire nut them together outside and shove one common wire into the 'hole'. How it's made secure mechanically is not apparent from the photos. It must be secure and not grounded.
There must be another wire to complete the high voltage circuit? Not shown.
If the ground is the 'other' conductor, then you've got a bit of a dangerous situation there.
Get a new pump that works on hot and neutral.

D.
The two wires go into the same hole, but I suspect they're connected separately inside. I don't know how by looking at it. Probably wouldn't try chucking them in and connect, may do more harm than it is.

I've *accidentally* cut some of the white plastic from the 'hole'. I think that was meant to isolate the grounding from the hot. In any case, it doesn't seem like the solenoid is meant to be opened.

This is almost similar to the NH26 pump.
http://cdn.instructables.com/F0H/I9RI/F ... .LARGE.jpg

OldNuc
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#9: Post by OldNuc »

The edges look to be rolled over which pretty much prevents disassembly without machinery and definitely makes reassembly a trick.

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erics
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#10: Post by erics »

One little item you should know . . . take it with a small grain of salt. Those early Ulka pumps were NOT internally fitted with a diode and relied upon an external diode to block half of the AC sine wave.

I BELIEVE that if the new pump does not work at all, simply reverse the connections at the pump.
Skål,

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

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