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Procon pump repair/overhaul..

Postby gor on Thu Aug 02, 2012 6:40 am

Hi there,

For a long time I had the impression that the Procon style of pump was not an easily repairable item. Well, being a curious type of guy I decided to investigate further. This involved pulling the pump apart, inorder to discover the sequence of events needed to successfully separate the components. I literally destroyed the first pump on the first attempt.

Image

At the moment, I am soaking the inner components in acid to see what effect (if any) that has. If the acid
has no effect, than it would be possible to dunk the brass housing and pump innards when de-calcifying in
acid. This would have the added benefit of not needing to remove the innards, as this is quite difficult without the right tool. It would also simplify the process of an overhaul.

The components that need to be replaced when repairing the pump are:
O-ring
Bearing

If the disassembly is done without damage (to the innards) than overhauling a pump looks pretty simple and easy! Would love to hear some thoughts you guys have about this.

Cheers,
Gor.
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Postby stuartmac on Thu Aug 02, 2012 8:32 am

i took mine apart when i replaced it with a fluid o tech. but i had a heck of a time getting the old one apart i destroyed it as well.
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Postby gor on Thu Aug 02, 2012 9:00 am

The hardest part is getting the bearing out. A bearing puller that attaches to a slide bar hammer would make that part easy. I have that type of attachment but I need to think of a way of doing it using easy to get stuff like threaded rod and nuts/washers etc.. That way if pump repair is going to be done by the average Joe, he/she can do it with minimal cost.

Also, I have been looking at the vanes that have come out of the pump. They have minimal wear on them at the point of contact. However, I also don't know what kind of work the pump I pulled part has done so wear on the vanes and liner could also be an issue. These seem to be made from a carbon/graphite material as they are very light in weight (hope they hold up in the acid bath!!). Doing an internet search didn't bring up any part source for the vanes, liner and end plates to the pump which are all made of this material. If anyone has any thoughts about where these could be sourced, please chime in.

Doing a search also reveals that there are a few places that will recondition your pump if you send it to them.
Don't know what the cost is.

Gor.
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Postby civ on Thu Aug 02, 2012 2:22 pm

Hello:

gor wrote:The hardest part is getting the bearing out.

Like in any motor driven rotary pump, the bearings are is a critical part.
gor wrote:... the vanes that have come out of the pump. They have minimal wear on them ...
... wear on the vanes and liner could also be an issue.


I think that the vanes are the main issue.
I think the vanes and the liner are what the pump depends on to work properly ie: a certain very tight tolarance. The fact that they are made from the type of material you describe (graphite?) makes me think that they turn tightly pressed on the liner the set of springs you can see in the picture below.

This is an exploded view of a Procon which clearly shows the complexity of the thinguie.
It's probably much the same as any other model of their line.

Image

IMHO, I'd say you are better off sending it in to Procon or one of their reps for a complete overhaul. They have all that's needed (tools and replacement parts) to do it. I'm sure it costs much less than a new one and will probably give you a nice warranty on parts and labour.

Cheers,

CIV
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Postby gor on Fri Aug 03, 2012 12:40 am

Hey CIV,

Thanks for the reply. You're right when you say that the bearing is critical in the proper operation of the pump. It is also a very cheap part and easily obtained. Furthermore, it might be possile to replace the cheap one used with a higher quality one that might last a little longer than the original. If it can be easily removed than it is eaven simpler to put it back in. You could carefully tap one in or press it in, between a set of jaws on a bench vice.

The vanes are held in place with a set of pins, and not springs. As a result they are not being pressed against the liner walls so I think for this reason, wear on the vanes would not be an issue. They kind of just float in the axle/liner cavity. In fact, once they have settled in from new, water which is being pumped would act like a lube and cushion the vane/liner contact surface (on a microscopic level). The only issue I can see is calcium build up, which would infact cause the vanes to wear at this iterface. If you could decalcify at an early stage in a pumps life, would it be able to last a longer time?

Image

Image

The above pics show the results from an insanely strong acid solution (hydrochloric/ or muriatic as you guys call it?).

The liner survived!! I therefore think it woud be possible to dunk the whole brass housing (complete with rear plate and liner in place) into acid. The liner is hard to remove wthout the right tools, so one less step is a good thing!

I have a totally seized pump on hand, shaft doesn't rotate, bearing rusted out, solid calcium deposits visible. I will go ahead and try to decalsify the pump with liner in place to see if this will work. It will also be a good time to see if any wear has happened on the innards of a very used unit. Will let you know about the results.

This topic also seems to not be getting any responses? I am also like you guys, for years being told 'it is not possible'. Well the cost to actually do it is minimal compared to US$180 for a new one! Price would be: cost of a bearing and O-ring. Oh, and also your time.
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Postby civ on Fri Aug 03, 2012 7:19 am

Hello:
gor wrote:Thanks for the reply.

You're welcome.
gor wrote:You're right when you say that the bearing is critical ...

Indeed. I'd say that for anything that turns at that speed and on bearings.
gor wrote: It is also a very cheap part and easily obtained.
... might be possile to replace the cheap one used with a higher quality one that might last a little longer than the original.

Yes, I have seen that to be possible.

Some bearing manufacturer catalogs are quite populated: for the same size shaft and bearing well you have many different models and qualities.

But bearing removal is a tricky and delicate biz.

For many bearing assemblies, it's just a matter of patience, a vise, a block of wood and a wooden mallet but for others (been there, done that) there are special tools without which the end result is most probably a damaged shaft and/or bearing housing that has been rendered useless during the extraction process.

I take it that the parts labelled 'front' and 'rear' bearings are not regular 'roller bearings'?

gor wrote:The vanes are held in place with a set of pins, and not springs.

Quite so, my bad.
Sorry for that.
gor wrote:... wear on the vanes would not be an issue.

I'm not too sure about that.
My idea is that when they wear past a certain limit, the pump won't work or have enough pressure.
What I recall having read somewhere is that factory rebuild (usually?) implies new vanes, liner, seals and bearings.
gor wrote:The only issue I can see is calcium build up ...

Yes.
I think that calcium deposits and bearing wear are the two main problems with these pumps.
gor wrote:If you could decalcify at an early stage in a pumps life ...

I guess that like with any other artifact subject to water calcification, yes.
gor wrote: .. insanely strong acid solution (hydrochloric/ or muriatic as you guys call it?).

Yes. Muriatic is the street name it goes by here.

The problem these days is that it is used (just like acetone and other similar chemicals) by the usual suspects to make powder that some people like to snort, so it hard to impossible to get it full strength here in AR.

Beware the fumes the full strength stuff gives off as even metal parts in close vicinity can be affected by them, not to mention your OEM breathing equipment. (again, been there and done that).
gor wrote:The liner survived!!
Good thing.
... possible to dunk the whole brass housing (complete with rear plate and liner ...

I guess that would be possible.
gor wrote:... liner is hard to remove wthout the right tools, so one less step ...

Indeed ...
One less step but more than anything, a part with no available spare that won't get damaged in the process. =-)
gor wrote:... a totally seized pump on hand, shaft doesn't rotate, bearing rusted out, solid calcium deposits ...
Will let you know about the results.

Please do.

I have an Italian made pump from a factory that went south years ago (Vibropompe) which I am not using but it is quite old and has had it's share of usage. It's almost identical to a Procon and probably needs an overhaul.
gor wrote:... cost to actually do it is minimal compared to US$180 for a new one ...

I'd say you have to compare it to the cost of a factory overhaul + SH to and from.
And add to the equation the warranty you'll probably get on parts and labour from the factory.

But, like you, I enjoy the challenge and have never liked the idea of 'it can't be done' just because no one else has. The 'mechanical DIY geek' factor is important to people like us two, but bear in mind that not everyone has the time, tools, manual ability and most important, curiosity, to undertake this type of thing.

Thank you for posting the data and the photos.
Please keep us posted on the results, I am most interested.

Cheers.

CIV
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Postby erics on Fri Aug 03, 2012 9:19 am

And then there is the question of parts availabilty (ZILCH), in particular the mechanical seal assembly shown in the illustration which CIV (Carlos) provided. The installation of a "better" bearing is not necessarily a good idea as the subject of bearing selection depends on several factors, cost being but one of those.

A noted repair facility here in the US are these guys: http://www.jcbeverage.com/index.html . Cost is around $35 plus shipping. Equivalent facilities are likely available worldwide.
Skål,

Eric S.
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Postby civ on Fri Aug 03, 2012 3:04 pm

Hello:

erics wrote:... repair facility here in the US ...
... around $35 plus shipping.

And there you have it. =-)
Can't get much better than that.

erics wrote:Equivalent facilities are likely available worldwide.

I'm not too sure that it's so 'worldwide'.
That aside, for a US resident it's easy peasy unless the shipping gets too expensive.

Cheers,

CIV
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Postby erics on Fri Aug 03, 2012 3:42 pm

http://www.proconpumps.com/pages/Exchange-Centers-%7B47%7D-International-Reps.html

YIKES ! They're even in Brazil :) . . . but not during Mardi Gras :)
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Postby gor on Fri Aug 03, 2012 10:14 pm

Hey guys,

Thanks for the responses! Just some more photos to add to the discussion..

Image

The actual bearing used leaves a lot to be desired.

Image

This is the front bearing which forms an enclosure with the liner and in which the shaft rides in. You can see the calcium build up on the inlet and exit ports, some of which has been scraped way with a screw driver.

I have read elsewhere that on re-assembly, cleanliness is of upmost importance otherwise a proper seal won't be made. Lube of any kind is not recommended on the liner components and alcohol to be used to clean everything. I will assemble a unit using this advice, as well as trying one with a dry lube such as graphite powder. The dry lube might make re-assembly easier.

Cheers.
Gor
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