How do I test a rotary pump

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JHath
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Postby JHath » Sun Jun 12, 2011 4:39 pm

I recently received a la Cimbali Selectron M27. This is my first serious attempt to get a machine working. It has been sitting for a year at least. It is not known when it worked last. My knowledge of commercial machines is limited. I am getting water through a flojet to enter into the inlet, but water is seriously leaking out between the pump and the motor that runs it. A light on the machine indicates the boiler is filling, but it is not. How do I test what is working? Any suggestions on what I should do? Any help will be appreciated.

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Randy G.
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Postby Randy G. » Sun Jun 12, 2011 5:46 pm

Water leaking out the back of the pump means the seal is likely blown. If it has been going on for some time it could damage the motor bearings. Prudence dictates that the pump and motor should come out for disassembly and inspection.
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JHath
Posts: 6
Joined: Sat Jun 11, 2011 8:24 pm
Real Name: Jim
Equipment: Wega Atlas EVD (2 group) Max 6.4 Grinder
Location: Medicine Hat, Alberta Canada

Postby JHath » Sun Jun 12, 2011 7:17 pm

There is no evidence of an ongoing problem. I pulled the pump off. Is the gasket a little white thing like an o ring inside the ?
There is a little gunk on the connecting shaft and area, but everything looks smooth and clean. I'll try to get photos up

JHath
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Equipment: Wega Atlas EVD (2 group) Max 6.4 Grinder
Location: Medicine Hat, Alberta Canada

Postby JHath » Sun Jun 12, 2011 7:34 pm

Here is a photo

Image

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cannonfodder
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Postby cannonfodder » Mon Jun 13, 2011 12:23 am

The pump motor should spin freely when spun by hand. The pump should also turn relatively easy. If it is leaking water from around the hub in your photo, you need to rebuild it, have it rebuilt or replaced. The only place you should have water is out the out side of the pump fitting.

PS: Those following this thread may want to reference replies to Jim's cross-post on CoffeeGeek.
Dave Stephens

JHath
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Joined: Sat Jun 11, 2011 8:24 pm
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Equipment: Wega Atlas EVD (2 group) Max 6.4 Grinder
Location: Medicine Hat, Alberta Canada

Postby JHath » Mon Jun 13, 2011 1:11 am

Thanks Cannonfodder

The motor and the pump both spin freely. The motor side opening has some clear grease in it. Is that normal?

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cannonfodder
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Postby cannonfodder » Tue Jun 14, 2011 2:35 pm

Yup, just lube for the motor. Where is the pump leaking?
Dave Stephens

JHath
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Equipment: Wega Atlas EVD (2 group) Max 6.4 Grinder
Location: Medicine Hat, Alberta Canada

Postby JHath » Tue Jun 14, 2011 3:09 pm

I was leaking were the two pieces come together (ie. under the band clamp). I cleaned it out and reconnected. What weight of grease should I use? Any specific brands, etc. ?

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Bob_McBob
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Postby Bob_McBob » Tue Jun 14, 2011 5:15 pm

Why do you want to keep using it if it's leaking? You will just end up with an expensive motor to replace as well. Adding grease isn't going to fix a leaky seal. You need to rebuild or replace the pump.
Chris

JHath
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Joined: Sat Jun 11, 2011 8:24 pm
Real Name: Jim
Equipment: Wega Atlas EVD (2 group) Max 6.4 Grinder
Location: Medicine Hat, Alberta Canada

Postby JHath » Tue Jun 14, 2011 5:31 pm

Hi Bob,
Thanks for the advice. Let me explain: On my first attempt to get this older machine working, I noticed a leak coming from where the pump meets the motor (ie., under the band connector). This happened at the tank fill stage. I am not terribly mechanically inclined. I took the pump off, inspected both connection points and cleaned (soaked) them. I have put it back together and it no longer leaks. From my point of view I do not know that the pump is actually broken. Possibly it was just a bad seal or loose connection. If you are reading something here that tells you it is broken please tell me. I am truly asking for help, but don't want to unnecessarily replace a pump. Thanks