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Trojan Hydraulic Pump

chansey

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Mar 21, 2010
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171
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New Mexico
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Retired Project Engineering Manager
I Need advice from a hydraulics guru to assist in finding parts for my 1989 Trojan Loader. The 1500Z and 1700Z loaders use the same hydraulic pump. According to Weser Pumpen, the current pump is WP340-3 and only available in Germany at $500 more than I paid for the loader.

The pump flange (pump shaft housing to transmission) had a seized bearing and damaged the housing. The previous owner must have had problems as well because the shaft that connects the trans to the pump is about 1/2" short and the shaft seal just floats.

I'm hoping someone knows where to find a replacement and if not, steer me in the correct direction even if it requires replacing the pump and re-plumbing. The pump is a 3 section pump with a manifold over all three pressure ports. I don't have the pump specs

DSC00161.JPG DSC00160.JPG DSC00164.JPG DSC00159.JPG

Additional Pics next page
 
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chansey

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Mar 21, 2010
Messages
171
Location
New Mexico
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Retired Project Engineering Manager
More pics

DSC00163.JPG DSC00165.JPG DSC00166.JPG DSC00168.JPG
The 3 rings shown with the shaft should NOT be part of the Assy. Trans side of shaft is 14 spline (31.12mm) and pump side is 16 spline (17.70mm)
All 3 pressure ports are the same size and the manifold goes over all three ports
 

lantraxco

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Jan 1, 2009
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Elsewhen
A) What's wrong with the old pump?

B) Is the shaft short or just positioned incorrectly due to problems in the housing or the wrong bearing?

C) Which end did the seal live on originally? Both sides are wet.
 

chansey

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Mar 21, 2010
Messages
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Location
New Mexico
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Retired Project Engineering Manager
Lantraxco,

The flange (part that bolts to the trans) was leaking badly. Took the pump out and the shaft was wobbly--- not good. Removed the flange from the pump and the
bearing was destroyed and the remaining portion of the bearing was seized on the shaft. Only pieces of the seal were found.

The seized bearing chipped away at the stop in the flange. There were 3 large washers on the shaft just behind the seal. The shaft appeared to be short because it was not fully engaging the gear drive in the first section of the pump and the seal was at the beveled portion of the shaft. The sealed bearing should be a tight fit in the flange ... it is loose and spins.

There is no seal on the shaft portion that goes into the transmission, just the sealed bearing and the snap ring. The shaft seal is next---- that's all there is.

The previous owner must have had the same issues because there were no bolts holding the pump in place. Installed bolts, used the loader for a while until the leak
became a gusher. The pump sections were all working well and had power and pressure.

Weser Flange-2.JPG Weser Flange-3.JPG

The problem lies in the flange assy. Either the flange or the shaft is an incorrect part and possibly both.
 

lantraxco

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Elsewhen
So, did you install that sealed bearing on the old shaft then? It's either wrong or not on all the way, should be a snap ring groove to hold the bearing I should think. Also, why a sealed bearing? The transmission should be wet, so let it lube the bearing. Sure would be nice to have an original parts breakdown, eh?

Take a much close look at the bore of that flange, looks to me in the picture there's still a bearing outer race in there?
 

chansey

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Mar 21, 2010
Messages
171
Location
New Mexico
Occupation
Retired Project Engineering Manager
We obviously don't know each other, however I do have sufficient ability and skills to trouble shoot the issue. I worked as a Plant Engineer for 35 years and currently own 5 pieces of earth moving equipment and perform all maintenance and repairs myself. I also hold 2 US Patents and received a Civil Engineering Grant at UNM. I am also well on my way to age 72.

Here is my original Post/Request,

"I Need advice from a hydraulics guru to assist in finding parts for my 1989 Trojan Loader. The 1500Z and 1700Z loaders use the same hydraulic pump. According to Weser Pumpen, the current pump is WP340-3 and only available in Germany at $500 more than I paid for the loader.

The pump flange (pump shaft housing to transmission) had a seized bearing and damaged the housing. The previous owner must have had problems as well because the shaft that connects the trans to the pump is about 1/2" short and the shaft seal just floats.

I'm hoping someone knows where to find a replacement and if not, steer me in the correct direction even if it requires replacing the pump and re-plumbing. The pump is a 3 section pump with a manifold over all three pressure ports. I don't have the pump specs"

I will answer the questions in the previous post in the order they were asked.

The bearing and seal were crossed by Parker Hydraulics. Yes the snap ring is there to hold the bearing. There is .003 to .005 of wear in the flange and it is enough to allow the bearing to spin. There is also a machined ridge for the bearing to stop when seated.

The transmission and the hydraulic system are independent of each other and have separate fill ports. If the fluid from the hydraulic pump is permitted to enter the transmission, it becomes over-pressurized and dumps the oil out of the breather on the transmission and of course, empties the hydraulic tank. I don't know if the sealed bearing is a backup to the seal to keep fluid from entering the transmission. The seal is a problem because if it is seated until it bottoms out there is very little shaft engagement by the seal. The shaft is too short or I need a seal with another 1/2" of length so the seal fully seats on the shaft.

The inner bore of the flange was damaged by the seized bearing. That is the damage seen in the photo. The bearing was completely gone except for the inner sleeve that was friction welded to the shaft. Took a while to remove the piece off the flange.

There is no saving the flange because of the damage. Even the bearing sleeves in the flange for the gear shafts are damaged.
 

lantraxco

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Didn't mean to get your hackles up, and I am suitably impressed by your credentials and experience. No we don't know each other but I'm guessing if we shook hands and had a chat face to face we'd be friends, it's the written word that fails to carry the tone and attitude that gets us wound up sometimes. That and as I have been told, I am a miserable SOB. Genetic, what can I say? What I would like you to understand though is my life experience has been forty years of loggers, contractors, tugboat owners and equipment dealers either too poor, too cheap, or too stubborn to pay for new parts and/or the kind of machines where replacement spares simply were not available at least in a timely manner. I have had much success with making things live when they shouldn't and more often than not improving on OEM designs because I could and the few dollars it cost didn't have to be approved by some accountant.

So, at this point there is no known source of replacement parts for the old pump or I assume you would have found it. It is possible somebody on here will chime in and then we'll all be happy.

You can check with these folks for used bits, worth a try:

https://www.machinerytrader.com/lis.../list/category/1060/wheel-loaders?Manu=TROJAN

Now, in the meantime the least cost option if it were possible would be to repair what you got I think.
First is the shaft is too short? Maybe. Or maybe it's just sitting too far toward the transmission end. Have you measured the female spline depth in the pump shaft to see where the shaft would bottom out? Maybe it's not a 1/2". I asked about a snap ring groove, I meant but perhaps did not state it clearly, a groove in the shaft for a ring to retain the shaft in the bearing, not the large one that retains the bearing in the flange. I could be all wet, but let's look at all the possibilities here, as obviously some ham handed wrench has cobbled things up at least once before, and bearing crosses ain't always right. Trust but verify, especially with parts people (I was one of those too). You only need about an 1/8" of shaft surface past the seal lip to be comfortable.

You say there's no saving the flange, but hell there's meat galore there, the bushings can be had or made from something close and it won't cost much to sleeve that flange to make the bearing a correct fit again. Any decent machine shop whip that out for you. Maybe pull that bearing back off, chuck the shaft up in the lathe and turn the shoulder back until you get the spacing where you like it. More than one way to skin a Maus.

I would still lose the seals on the bearing if it is in fact the correct size, but that's just me.

Anyway, hope you get it back together.
Lanway
 

Mike Van

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May 23, 2011
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Kent Ct.
There are all kinds of machine scrap yards across the USA - Have you searched there? That machines not that old, seems there would be a few being parted out.
 

chansey

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Mar 21, 2010
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171
Location
New Mexico
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Retired Project Engineering Manager
Mike,

I've called everyone I could find. Seems like trans and pump are first to get pulled.

I've also called many of the pump manufacturers too and haven't come up with anything.

Thanks
 

chansey

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Location
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Retired Project Engineering Manager
Yes ... they were unable to ID old number or new part number.
Actually went there first.

Front Flange-Commercial.JPG Found this ... may be the ticket. Notice the sealed bearing ???
 

chansey

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New Mexico
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Retired Project Engineering Manager
I didn't provide a link or source for the parts. This company has a wide selection of repair parts and located in CA

http://www.intlfpa.com/

For some reason they don't come up on search engines
 

chansey

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Mar 21, 2010
Messages
171
Location
New Mexico
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Retired Project Engineering Manager
UPDATE - Trojan Hydraulic Pump

Still no source on a pump. Finally got thru to Tech Support at Minnpar. Appears the pump has been updated 3 times and Minnpar doesn't have any.

Took the pump completely apart and the results are not good. Besides the issues with the flange and shaft, it appears as though the input shaft caused vibration in the entire pump. All of the bushings have chatter wear on each gear bushing ...... little gear wear on section 2 & 3. The main pump gears are another story. The gear housing has some "hot spots" on it as well as severe wear from the input shaft flopping around. The gear edges are sharp. Signs of severe wear.

The main pump flows at 33 GPM at 2500 PSI and 2100 RPM, The smaller section flows at 23 GPM. At this point I am leaning towards a retro fit to a pump that is readily available. Adding flow and pressure control should not be a problem and would eliminate the 125 LB manifold that is on it now.

Has anyone completed a retro fit on a Trojan or similar situation? Suggestions welcome.
 

RZucker

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UPDATE - Trojan Hydraulic Pump

Still no source on a pump. Finally got thru to Tech Support at Minnpar. Appears the pump has been updated 3 times and Minnpar doesn't have any.

Took the pump completely apart and the results are not good. Besides the issues with the flange and shaft, it appears as though the input shaft caused vibration in the entire pump. All of the bushings have chatter wear on each gear bushing ...... little gear wear on section 2 & 3. The main pump gears are another story. The gear housing has some "hot spots" on it as well as severe wear from the input shaft flopping around. The gear edges are sharp. Signs of severe wear.

The main pump flows at 33 GPM at 2500 PSI and 2100 RPM, The smaller section flows at 23 GPM. At this point I am leaning towards a retro fit to a pump that is readily available. Adding flow and pressure control should not be a problem and would eliminate the 125 LB manifold that is on it now.

Has anyone completed a retro fit on a Trojan or similar situation? Suggestions welcome.

The pump you have appears to be a Commercial Shearing pump with a universal nose mount. I would find a local hydraulic shop with a reputation for solving problems. It can be done. I have done a few conversion jobs on several pieces of equipment that were "impossible" with the help of a Real hydraulic shop with milling, boring, and other machining expertise.
 
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chansey

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New Mexico
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Retired Project Engineering Manager
RZ

It is a German pump made by Weser. I have even chased the pump thru The Netherlands, France , Spain and UK trying to find parts.

The flange is std SAE B and C and that's where commonality ends. The shaft is non-standard length and the gear sets are non-standard metric or SAE Imperial.

I will be better off finding a pump that bolts up and then find, make or fab manifolds and add flow and pressure hardware where needed. I have 3 days of work for the loader and in a bind at the moment.
I'm work finding a pump, however for the time being, I will have the shaft polished, replace the gritty bearing and install a double lip seal. All six bushings need replacement. I'll re-install the pump and see if I can get my work done and then park it until I get the parts for a conversion.

I agree with you that there are many ways to work around a problem. Thinking of a solution doesn't cost much.
 
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