Tractor hydraulic issues

[M.Magis]

I'm having intermittent hydraulic issues, and was hoping someone may have an idea where I should be looking to fix the issue. It's a JD 2550. Last Sept while cutting hay, the hydraulics slowly started going away. I managed to get back to the barn just as I was losing all steering. Over the next month or so, whenever I started it they still didn't work, but had too many things going on to mess with it. I started it in Nov and everything worked fine. A friend who's much more experienced in tractors suggested the sump filter may have been clogged, so I pulled it this spring and while it wasn't clogged, there was a lot of junk that came out right behind it. I hoped that had been the problem, but since it was still working fine I couldn't be sure. I've used regularly all summer, but while mowing hay (finally) on Wednesday, they quit again. I pulled the screen again last night, but it was clean. While letting it run in the garage and trying to working the steering, it did suddenly start getting some pressure again. Not enough to operate (loader chattering, going slow), but something. At this point I'm not sure where to start. There are two pumps, the main and the steering. I'm not getting any warning lights, the only way I know it's going out is the loader not working. Any ideas?
Thanks for any suggestions.

 

[Angus Cowman]

Does that tractor have the screen in the side of hyd res down under the axle on the right side
It is down low on main rear housing ?

 

[M.Magis]

Yes, I should have said screen instead of filter. I pulled it again and everything looks okay. I have the tech manual, and in one diagram it suggests there's another screen somewhere, but I think it's illustrated poorly.

 

[Nesikep]

You lose both the steering and the hydraulics? if that's the case it nearly has to be something in the pickup system if they share that.. find that other screen and check it

 

[M.Magis]

Yep, I lost everything. But the steering is the last to go. When I first noticed the loader not working, it took at least 10 more minutes before the steering quit. Not sure if that means anything or not. Now if I start it and work the steering wheel, it'll build a bit of pressure. Just not much.

 

[Nesikep]

a lot of repair manuals have a hydraulic schematic.. perhaps ask a dealer to email you that page of the manual if you don't have it, then look for things that are common to both systems..

 

[highgrit]

How about hooking a pressure gauge up somewhere to see if the hydraulic pump is producing pressure.

 

[Nesikep]

if both systems are dying, I'd bet it something before the pump... airlock? cavitation? plugged screen somewhere?, pinhole allowing them to lose prime? low fluid level?... I'm just thinking out loud of various possibilities...

 

[jltrent]

Seems that is a pretty common problem in older JDs. Somebody ought to have some good info. A neighbor had a 2840 with a loader and he spent a pile of money on the hydro system I know that.

 

[Craig Miller]

Sound like low fluid. Since it happened while baling id say you had a small leak on the baler drained your fluid. I know you checked that though. Id lean toward what nesi is saying in cavitation/airlock. Breather stopped up maybe.

 

[M.Magis]

My original plan last year was to pressure test the main pump, but then it started working. The way it's been intermittent, airlock/cavitation makes sense. The tech manual has very detailed schematics, though they make me think I'm in over my head. I'll go through them again and see if I can find a starting point. I appreciate all the advice.

 

[Angus Cowman]

You might go on the agtalk forum there is lot of guys on there that have alot exp on things like that

 

[M.Magis]

This is old, but thought I'd give an update since everything is up and running now. It's unlikely anyone else has to problems I had, but just in case. Took it to a Deere dealer since they have a few mechanics very familiar with these systems, and we had gotten to the point we were just guessing. First problem was the hydraulic clutch, which was our guess. It supplies fluid to the main pump, which explains why it was acting like it was. The other problem was much more severe. At some point in the past someone had tried to rebuild the Hi-Lo, and didn't know how. Things were in the wrong order, and they left out some thrust washers. Everything in there was basically shot, and the entire system was full of metal dust. They were surprised it even moved as bad as it was. You can probably guess what Deere hydraulic parts cost, and I can't say it was even worth fixing it. But it was that or leave it in the field to rust, so I bit the bullet.

 

[Highacres]

Just saw your post about your JD 2550 hydraulic issue. I had a similar problem in my 2550 with cab. After running a while I would lose hydraulics and steering at mid to lower rpms. Put up with it for a few years but it got worse and finally wouldn't drive the hydraulic pump on the sprayer after it got warm. I checked the sump, took off the front hydraulic pump and had it bench tested. It spec'd out fine. Finally took it to a good Mennonite mechanic who split it and found a broken internal steel hydraulic line. He changed the hi/lo & pto clutch while it was apart. No more hydraulic issues. Hope this helps.

Rick Burt