The old 425 again…LOL

[Modrob]

Seeing our old unit sitting with the failed pump, I keep thinking about it and what might be able to be done with it…thought I’d ask your opinions…

I know that a new tram pump (replacement for the Sundstram Series 15) is terribly expensive, and again this is an old, 2001 unit with a lot of hours on it. But, I’ve kept it up in the last couple of years with some motor work. Hydraulics? That’s a new world for me…
I did take the old one apart—or a lot of it. And found most of the 9 pistons damaged, along with the spacer ring. All else looks fine best I can tell. My initial exam tells me I could get it together with these new items and it might again work. Hard to find parts and when I do, they are astronomical as well. (250-350 and up for those little pistons) Maybe get lucky and find a used one, etc…and possibly end up having it running again, but mostly to sit, as the new 425 handles everything well…

Option 2: Could the pump be replaced with a different model? I’m guessing that it’s not possible to move the unit without a pump…
Solving the movement thing, I thought of it becoming a dump wagon, dump bed, etc.

 

[ponytug]

Seeing our old unit sitting with the failed pump, I keep thinking about it and what might be able to be done with it…thought I’d ask your opinions…

I know that a new tram pump (replacement for the Sundstram Series 15) is terribly expensive, and again this is an old, 2001 unit with a lot of hours on it. But, I’ve kept it up in the last couple of years with some motor work. Hydraulics? That’s a new world for me…
I did take the old one apart—or a lot of it. And found most of the 9 pistons damaged, along with the spacer ring. All else looks fine best I can tell. My initial exam tells me I could get it together with these new items and it might again work. Hard to find parts and when I do, they are astronomical as well. (250-350 and up for those little pistons) Maybe get lucky and find a used one, etc…and possibly end up having it running again, but mostly to sit, as the new 425 handles everything well…

Option 2: Could the pump be replaced with a different model? I’m guessing that it’s not possible to move the unit without a pump…
Solving the movement thing, I thought of it becoming a dump wagon, dump bed, etc.

Hunting down a similar used variable volume pump might be possible, but of course comes with the caveat of "what happened to the donor unit in the first place"? If your system, or the new to you pump has any debris inside, I think that you run the very real risk of catastrophic failure of pumps and motors. Adding new high pressure filters to capture potential debris aren't cheap, and bidirectional filters for the drive circuit especially so.

I think that it is easy to underestimate the effort, not to mention cost, involved in flushing every hose of debris, every motor, every cylinder, and every valve. There is the very real possibility that you do not get 100% of the metal debris out and it comes loose after starting repaired version up and rattling it around for a few hours.

Frankly, I think doing a conversion to all electric is probably easier and cheaper.

All the best,

Peter

 

[ponytug]

In general, I am all for fixing up old equipment and getting them running, but for $3k-ish you could buy a dedicated dumper crawler with a 3,300lb capacity. E.g.

New 2025 IR IRD25 Crawler Dumper

New 2025 IR IRD25 Crawler Dumper Fuel Type Gasoline Additional Features 9" Rubber Tracks, Seat

bid.rollerauction.com

There are bigger ones available from Yanmar and others, and cheaper for direct import.

All the best,

Peter

 

[muncybob311]

WOW! I want one of them!!!

 

[ponytug]

WOW! I want one of them!!!

I agree! I are pretty neat units. I had no idea that they had gotten so cheap until I looked for @modro. The Yanmar units that I am more familiar with are a lot more expensive. I have seen them used for remote construction work as they have much better flotation than wheeled vehicles, and far more maneuverable.

All the best,

Peter

 

[Modrob]

Hunting down a similar used variable volume pump might be possible, but of course comes with the caveat of "what happened to the donor unit in the first place"? If your system, or the new to you pump has any debris inside, I think that you run the very real risk of catastrophic failure of pumps and motors. Adding new high pressure filters to capture potential debris aren't cheap, and bidirectional filters for the drive circuit especially so.

I think that it is easy to underestimate the effort, not to mention cost, involved in flushing every hose of debris, every motor, every cylinder, and every valve. There is the very real possibility that you do not get 100% of the metal debris out and it comes loose after starting repaired version up and rattling it around for a few hours.

Frankly, I think doing a conversion to all electric is probably easier and cheaper.

All the best,

Peter

Yes sir, I understand. And agree. And yet…LOL here I am, STILL entertaining thoughts about it. Many times I haven’t done things in a “smart” way, but in many cases I’ve had success. And yes, it usually cost me more in dollars, and time. And there have been times when I got so far in and it finally came to me I wasn’t going to win, and then I’d chuck the project. (one recent case was a danged Keurig coffee maker—that joker had a complex system—every time I thought I’d found and fixed the problem, it would work fine a cycle or two, then back to the problem. Lots of on-line time researching and trials. The wife kept insisting to just “throw it away and I’ll get a new one.” Egads! Just like that, throw it away? Perish the thought! LOL…in the end, I had to admit defeat. And face her. LOL But…shhhhhhh…don’t tell her that I still have it tucked away in a box…just in case…LMAO)

Most of the time I look at things like this 425 and figure, if I can spare some time from other things, and spend a little money, I might have success, or even a limited success. I weigh it out in my mind, and usually I’ll end up in the hole to some degree, but I always gain some knowledge and appreciation on how things work. That’s valuable to me, especially with my aging and the mind not working as well as in the past. I feel I have to keep challenging it, or I may lose faster. It’s clear that this unit is going to cost me. And, it could work again, maybe a short time or longer time. But I was thinking of making a small effort of it and MIGHT get lucky and get a little more time with it. But I don’t expect it to ever be at the level/functions it once was. Heck, I’d even settle for being a “toy” just for a grandson to ride around. LOL…
But to let it sit, rust away. You know it’s not worth much to others to sell outright, but feels more worth with us. And selling parts? Again couldn’t get back the worth we feel. And we really don’t have anything else to use the parts on either. I guess if I had a huge building with good space, I could deal with storing it away—a junk “museum” of sorts! LOL my initial thoughts have been try and fix the pump, clean everything up best I could, and see what happens. It might work, some, or a lot, or blow up right away. Kind a game of chance that costs quite a bit more than a lottery ticket or slot spin…So, what to do when you don’t want to do the “smart” thing? Haha…
Tell me more about your “conversion to electric” thoughts please.

 

[2manyrocks]

Strikes me as a case of the PT essentially being one big hydraulic system.

Even if you found 4 electric gear motors of sufficient power, then you need an adequate battery power supply.

Dont know how you would steer without something to power the steering cylinders.

 

[Modrob]

@ponytug
Just had another thought! (Oh lort!) I have another lofty project in mind—I have a HF towable backhoe/trencher that’s a handy machine. However it could be greatly improved with some kind of propulsion system to maneuver it around on its own. Wonder if the 425 wheel motors (2) could be used? Maybe too large for the backhoe’s hydraulic system? It would feel much better if I could at least use some parts off the 425 to improve other things we have…

 

[2manyrocks]

Suggest you look on youtube for videos of the Fland Fl45 chinese made articulating loader. It uses a mechanical propulsion system that will give you another perspective on the challenge of converting a pt425 to something else.

I would lean towards making the HF backhoe an attachment to move around with your new Pt425 instead of trying to add a propulsion system to the HF backhoe. I think that is more likely to be successful.

 

[ponytug]

@ponytug
Just had another thought! (Oh lort!) I have another lofty project in mind—I have a HF towable backhoe/trencher that’s a handy machine. However it could be greatly improved with some kind of propulsion system to maneuver it around on its own. Wonder if the 425 wheel motors (2) could be used? Maybe too large for the backhoe’s hydraulic system? It would feel much better if I could at least use some parts off the 425 to improve other things we have…

The world is your oyster! Have fun. I think it is a great goal to challenge my mind, so if you want to do the same, go for it. But if it were me, I would build new. If you really want to, go for it, but I would add a suction filter, or a return filter for every single pump or set of return circuits. I personally think removing sub-micron debris is hard.

Someone here did an electric conversion of a PT and reported that they really liked it.

I agree with @2manyrocks that if it were me, I would use the PT to move the backhoe around as that seems to me to be a lot less work and doesn't get into having to clean debris out of reused parts.

To me, that's the general problem with reusing any of the hydraulics from the old PT; I think that you would have to strip them down, flush them out, and perhaps rebuild seals on some if you are lucky, and have to junk others because of the potential internal damage. If the original pump died without shedding metal, (and I don't think that there is any way to know that), then perhaps it might be possible to clean and reuse parts. But if there is/was metal in the hydraulic tank or in the suction filter, then I think that I would want to basically rebuild any part that I pulled from a donor machine. "Trust but verify", and all that. If that isn't done, then I think the risk is that the reused part then sheds metal debris in the new system and then the whole new system is toast.

On the Keurig, I know of some folks that bypassed the internal controls with a small PLC.

All the best,

Peter

 

[2manyrocks]

I recall someone posting that rebuilding hydraulic systems requires cleanliness on the order of surgery room cleanliness. While I suspect that may be an overstatement, it does serve as a reminder of how much of a challenge it could be to rebuild the PT hydraulic system. I have found it a challenge to rebuild hydraulic cylinders which are far more simple than the type of work you might be facing.

 

[Modrob]

Dang…awful strong evidence that I’m in over my head. LOL…I think now there is so much to know about how these hydraulics work, that I’d have to spend a lot of time TRYING to learn about these hydraulic systems. I believe I’m oversimplifying it, and that, I can see, would get me in a lot of mess the deeper I’d tear into this…
Again, many thanks for the straight-shooting.

 

[ponytug]

Terry at Power-Trac told me "open heart surgery clean". From my experience, it is a good description of what is needed.

Larger hydraulic systems often treat the tank as "clean" with filtered returns, a filtered refill nozzle and filtered breather openings. That limits the damage from a single component failure, but in the case of a drive pump failure scenario, that would still probably trigger a cleaning of all the hoses downstream, and a rebuild of all of the drive motors, i.e. the whole circuit. For a PT with a single suction filter, that means rebuilding the whole hydraulic system. Basically, going over all of the machine with the view that every component is dirty until proven otherwise by cleaning and disassembly.

@Modrob I'm not saying that disassembling a component such as a motor or a cylinder wouldn't be educational, just that it might not result in a working component the first time. I'd try looking around YouTube for some rebuilding videos. Cutting Edge Engineering Australia has a number of good videos on cylinder repair and rebuilding. I think that generally his technique is pretty amazing, and tackling a problem with "How would Kurtis do it?" is a pretty good strategy, though my hand eye coordination isn't in his league, nor my mechanical or machining knowledge.

All the best,

Peter

 

[oldnslo]

Companies like Attica hydraulics in Michigan or ETS Hydro in Memphis reman units and then have them for sale. I believe they have a “core” charge to get the old housings back.

Typically a complete rotating group with new bearings and seals is approaching the cost of a new pump. Normally not advisable to put different piston in old cylinders block and might not be able to even purchase piston as a spare part.

I am not sure if Danfoss still builds the Eaton 15 series but suspect you might be able to find a similar size replacement but would also suspect ports location and possibly sizes would change.

Yes on cleanliness being critical when working on hydraulics especially with closed loop hydrostatic drive since dirt just runs in the loop damaging the pump and motor(s) in that loop.

Best of luck on your decision

 

[MossRoad]

In general, I am all for fixing up old equipment and getting them running, but for $3k-ish you could buy a dedicated dumper crawler with a 3,300lb capacity. E.g.

New 2025 IR IRD25 Crawler Dumper

New 2025 IR IRD25 Crawler Dumper Fuel Type Gasoline Additional Features 9" Rubber Tracks, Seat

bid.rollerauction.com

There are bigger ones available from Yanmar and others, and cheaper for direct import.

All the best,

Peter

Away with your temptations!!!!

 

[MossRoad]

While I know it's tempting to try and rebuild the old PT425, as others have mentioned, and I agree, it's going to be very hard to salvage any of the existing hydraulic components and being completely sure 100% that you got all of the debris out of them from the damaged tram pump. All those little metal pieces not only just go somewhere, they score and eat the walls of the pump cylinders, and if they get out of the tram circuit, they damage the motors.

Having them all torn down, inspected, certified as undamaged, and then rebuilt could be costly if sent out. Doing it yourself would require some knowledge.

Cleaning out every hose and fitting on a 20+ year old machine you might as well replace the hoses at that point, because they're probably getting old, brittle, worn, etc...

So price the cost of a new tram pump, two new PTO pumps, 4 wheel motors, all the hoses and fittings, the hydraulic cooler, the valves and bodies, the rams, and anything else I forgot...

If you're dead set on doing it for fun, inspect that tram pump. You said you found the pistons damaged. Look at the cylinder walls where those pistons travel. I'd be surprised if they aren't scored. The price of replacement costs for everything inside of that pump, even if they could be found, would probably exceed the cost of a new pump.

Anyhow, while I'm generally a tinkerer with stuff like that and enjoy seeing how things work, I can show you a pile of dead snowblowers that I was gonna fix someday.... It wasn't worth the time and effort VS buying new on those units.

 

[Gravy]

In general, I am all for fixing up old equipment and getting them running, but for $3k-ish you could buy a dedicated dumper crawler with a 3,300lb capacity. E.g.

New 2025 IR IRD25 Crawler Dumper

New 2025 IR IRD25 Crawler Dumper Fuel Type Gasoline Additional Features 9" Rubber Tracks, Seat

bid.rollerauction.com

There are bigger ones available from Yanmar and others, and cheaper for direct import.

All the best,

Peter

Where does the mower deck go?

 

[ponytug]

Where does the mower deck go?

It is a pull behind model...

All the best, Peter