Hydro-Ax 670 Documents

[kiko]

I never have any problem getting them out with cab all the way untill the cable is tight.  The drive motor does need to come off in frame.  I remove the rear drive shaft completely because it will never get out of the way with one end undone. On center slip just undo ujoint on tractor side. I prefer to take the drive line out first so oil is not dripping on me from unplumbing the drive motor.  Once that top mount is out of the way remove two of the top bolts that hold the case halves  together and put a longer bolt in for the hoist chain. I mentioned this before , check for spline wear between drive motor shaft and input shaft. If you remove line item 15 , keep  orientation as it is, but unless you have bearing  failure on the top shaft , or if you replace the bearings you will not remove it. This goes without saying ,but if you replace the bearings, you will have to reset the end play. So keep up with where the shims came from. That applies to all three shafts.

[Tony Wells]

The main operator suggested that unslotting the cable and lowering the cab more would allow a straight lift, but I'm not keen on that idea. I'd have to round up something to support the cab, and that's just one more thing that could go wrong. And I didn't look closely after he mentioned that (I had already left for the day), but it seems to me the cab lift cylinder wouldn't allow that anyway so would have to be unpinned. I'm sure we can get it out without extraordinary actions.


I always try to work from the bottom up too, for the same reason. I don't care to get an oil shower if I can get out of it.

I've rebuilt about 100 or so automatic and manual transmissions from lots of vehicles and equipment over the years, so I don't foresee any problems. The owner/operator manual probably does not have such information as end play on those shafts, but I'll do some pre-disassembly checks to at least have starting points logged in case I decide to replace some bearings. I'd rather not spend the time on that if it's still within service limits, but again I doubt I'll have the factory numbers. I'll use experience and reason to make those decisions as I go if I don't have the specs. Shouldn't be a problem.

Drawing is a little fuzzy on item 15. Is that a bearing retainer? I'll match-mark it in any case. One thing about working on this, is that back at my shop I work alone, in a HVAC environment with my favorite tunes softly in the background. Now that it's officially shut down, nobody bothers me or even knows when I'm there working, so I'm undisturbed.

[Tony Wells]

OK, more on the trans. The tag calls it a Terrell MP300010 sn 01946 mfg 07-04

That's Durst Division of Regal Beloit Corp Beloit WI.

I have found nothing online about that transmission. I sent in a request for information to Durst, since I find virtually nothing on Terrell. Maybe Durst simply absorbed them and they do not exist as a separate entity any more.

Supposedly I have some young bucks working on the R&R so I can get to the insides. Sounds like half to a full day the way they work..

If anyone can point me to a source of an exploded drawing of this transmission/gearbox I'd sure appreciate it. Pictures of pages in a manual would be better than what I have. kiko, your pages are good, but may not be a match for this transmission. Good news though, according to Durst on their product line of speed reducers and drives, etc., is that they use a type of bearing that does not use shims to set up end play, and the shafts are removed without pressing, etc. This being not in their current line I don't know how true that is, but if so, it should make things simpler. If I need parts, I'll either have to make them from scratch, or find a source of junked transmissions.

Kiko, the guys still want to lay the cab on over. We have several telehandlers, and I suppose they could strap it off to one and lay it on over, but I don't trust that to hold for extended time. They could block it up I guess. I looked at the jack cylinder, and I'm convinced it would have to be unpinned to move the cab that far. I'm not crazy about that either. There are a few wires that weren't meant to stretch that far too. I told them I'd loan them my cherry-picker engine hoist so the could be gentle, but they are hard headed. I'm a consultant, but I may have to pull rank on them and force the issue. If I didn't have a messed up back, I would already have the thing apart on my workbench. Can't stand people who dodge work.

[kiko]

Every body has their own way, but I have never had to undo the cable or the cab jack cylinder to remove on of those trans/gearbox.  I always used a service truck crane. The chain or strap hooked to the gearbox would be long enough so the pully block was above the cab . Hard to explain.  Your gear box will have the shims as it is actually a Terrell. And you are right the diagram I have won't work for parts replacement numbers as it has Blount part numbers. But you gearbox will be about the same. I have purchased durst parts from great lakes power. There is a complete gearbox for sale on eBay. It is an MP300029 new for 1200, not sure what the difference in specs are between the two.

[Tony Wells]

Thanks for all the help, kiko. If everything goes right, I'll have it back at my shop late tomorrow. I have to take a turbocharger over to Shreveport for testing. Having problems with a Volvo A20 artic. Bad 2 piece exhaust manifold. Burned through, nothing to weld up and remachine even. So far, the only complete set I've found is in Spain, so trying to get settled on a price and reasonable shipping. After chasing a 460 excavator engine for rebuild, I'm growing a healthy hatred for Volvo machinery. At least I'm getting the 460 back this week, after sending it to the engine shop back in November. I just sat and made a list of my projects....23 items. Some minor, some quite involved. And I'm a disabled consultant. Sheesh! Plan is just to act as coordinator for the heavy stuff. I'm just not up to it any more.

I'll put up a couple of pics of what I find.

[Tony Wells]

Well, here it is:


 

It took about half a day to pull, as I expected. They did lay the cab all the way over. I just hope nothing got damaged in the process. I took a pressure washer to it, because they just dumped it on a pallet for me (dirty rats have a washer there, but just lazy or didn't want to help me). It was pretty dirty, probably from oil leaks coming from the motor above, and for sure from the output shafts.

Now that it's sitting on blocks on the floor, I can, with a little help from a dead-blow get it in both high and low range. It's pretty stiff, so there is definitely something going on. I have the drain plug out of it overnight so tomorrow I'll be able to split the case and see what there is binding. Judging from the condition of the control cable, whatever is making it stiff has been that way a while.

I think I'll forego just locking it in low range in favor of freeing up whatever the problem is, if I can, and then leaving it in low for this job but afterward I'll track down the cable and fix it properly.  Of course, with it back in service, no telling what will show up as the next problem. The splines on the drive motor are smooth as glass and I can just barely feel the ridge where the contact with the input splines starts. I'm calling it good. The input splines are also very smooth all around. I was a little concerned, at the age of this machine, but for all I know, all of that has been replaced recently. New seals on the outputs and away we go....I hope.

On the control shaft, there is an adjustment nut to limit linear motion, or end position. Any instructions on setting that up? Or is that just to keep the cable from pushing (or pulling) the shaft too far and rubbing on the face of those spur gears? That I should be able to set easily enough.

More pics tomorrow.

[Tony Wells]

I'll skip the ugly details, but I tore the propel motor down and found a piston with no seal ring. Well, a little update to the saga. I was able to get the rings overnighted to me. I cleaned everything up, polished all the scratches that were there. Really was not bad at all. Took a few tries to get the pistons and dogbone all aligned when assembling the cylinder block. The old arthritic hands and fingers just don't cooperate like they used to. But I did get it together and delivered. After a few test runs around the shop they decided to go take down a handful of trees and see how well it sawed and grabbed. It did very well. Unfortunately it has been raining on and off for a week or two and the operator drove into a soft spot and sunk it to the frame. End of tests. I left the scene at this point. The plan was to anchor an old milsurp 6x to a tree and winch it out. I don't know the details, but it seems to have propel issues again. I have a feeling they just pulled it out with it not running and not in neutral. That makes me think there is now some motor damage again.
So I'm on the hunt for another motor (used, but running hopefully), since getting parts seems to be a difficult problem to overcome, although I did find what appears to be a good supplier here in-state and within reasonable driving distance should the need become desperate. They say they stock a lot of Danfoss parts, among other makes. I just hate that the damage could be from something as simple as dragging the machine out of the mud. I had already told everyone involved that the machine could not be moved with it in gear, as I had locked the transfer case in low. They would not have been able to drop the driveshafts very easily, because it was sitting on the belly pan and sinking further. But they could have opened the lines or removed the locking collar I had out on the transfer case and taken it out of gear....or something. But the pressure was on, and I'm betting no one gave it any thought. I'll have to find out. They will be pulling the motor on Monday.

To Be Continued......

I'm kind of bummed about it. It was looking like a success story.