JD 5075 Steering Wheel turns freely after tires stop turning

[wpchrist]

Our John Deere 5075 was having hydraulic overheating problems. After 1-2 hours of using a hydraulic implement (usually a cx-15 batwing) the hydraulic overheat light would come on. Eventually we could barely raise the loader or implement without considerable RPMs. So we had a new hydraulic pump installed by the John Deere shop. We got it home and I noticed right away that the Steering Wheel turns freely and easily after tires stop turning. This was not a problem before the repair. Before the repair, the wheel would turn very slowly, with effort, after the tires stopped turning. Can this be related to the pump replacement?

I could still steer and everything else seemed fine, so I used the tractor to mow. However, after about 6 hours of mowing with the batwing, the hydraulic overheat warning came on again. Eliminating that overheat warning was the whole reason we brought it to John Deere in the first place. Is it possible that the steering issue is related to the hydraulic overheat?

Additionally, after the overheat issue today I checked the hydraulic fluid and it was quite a bit over full. I was surprised at this as the tractor had just come back from the dealer for the hydraulic repair that included a hydraulic filter /fluid change. Could this overfull condition lead to overheating?

Thanks in advance for any help.

 

[Texasmark]

I'd suspect the system needs to be burped and the shop may have put in the recommended amount of fluid but with air, it is measuring high. Run the FEL up and down, max to max, couple a dozen times and do the same with the steering...just get out in the pasture and lock to lock to lock to lock then try it. See no connection between over filling and what you have. Over filling will seep out of worn rear axle seals, transmission input/olutput, PTO shaft seals, type problems. IMHO.

I think I recall Tx Jim mention that air can cause overheating of the hydraulics, or excessive pressure on an unloading valve.....like maybe you hold your lift lever too long, or you are constantly lifting and dumping the wings, or you are on uneven terrain..... that may be it.....and the pressure on the cylinders is constantly increasing and decreasing (or trying to move causing the pressure to oscillate) as the wing moves/attempts to move up and down with respect to the rest of the mower.

 

[wpchrist]

Thanks Texasmark. I'm pretty sure you were right on point with the steering issue. After A day and a half of operating the tractor the steering was back to "normal." I did some research afterwards and learned that the hydraulic system on this tractor is self-bleeding, so I'm sure it just took a little time to work out all the air. The overfill situation supports that. As you mentioned, the second day after returning the tractor to service (the same day the steering resolved itself) the hydraulic fluid level was back to normal.

Now for the kicker: I attributed the fluid level returning to normal to just what you suggested. Namely the air in the lines was gone now and I was getting a "true" reading of just fluid, and not fluid + air. However, the next day after operating for about two hours the steering started making noise with every small correction. During the two minutes I noticed it and was asking myself if it was real or my imagination, everything stopped working. No steering, brakes, loader or wing. Of course I stopped immediately and shut off the tractor. When I climbed out and walked around the passenger side there was hydraulic fluid everywhere. And of course it happened as far away from the shop as I can get on that property lol. Fortunately I had an accomplice not far away on a side by side, so I didn't have to walk back. Long story short, twelve gallons of fluid later i started the tractor and fluid was spraying out of one of the connections between the hydraulic lines and the pump. I got the four bolts holding the line to the pump pretty tight. There was still a small leak, but it was good enough to get it back to the shop. I'll be tearing it apart Wednesday or Thursday once I get the seal from John Deere.

It's a bummer that we just paid a pretty big chunk of money to have that pump replaced. I expected more than two days of operation. But things happen. We've all left something loose or disconnected during a repair I guess. I suppose the bolts on that particular fitting didn't get tightened and fluid was slowly leaking out until the seal finally failed entirely. I wish I would have caught it sooner. Unfortunately small leaks aren't always obvious because we park the tractor in a grassy area that doesn't show puddles. Plus, I was probably a little too fast to attribute the drop in hydraulic fluid level to the air in the lines bleeding out. Lesson learned. Hopefully the new pump wasn't damaged when the fluid got so low. Everything seemed to operate normally after I filled it for the temporary ride back to the shop. So I'm hopeful.

That disaster aside, your explanation for the overheating got me to thinking about how I use the batwing. I mow a lot of levees and work the wings up and done steadily. Plus the edge of the levee isn't the smoothest, so the wing on the edge is sometimes ground-supported and other times supported by the cylinder. That could lead to the situation where the pressure on the cylinders is constantly increasing and decreasing. And because our hydraulics are set up so that one valve controls both wings, both wing cylinders would be affected. As the levee drops from under the wing on that side, that wing lowers a little and raises the other wing slightly. Maybe that caused the initial problem? But we have had that tractor and batwing for four years without a problem, so I don't know. I guess once I get this leak fixed I'll keep a closer eye on how the terrain might be affecting the cylinders. If the overheat continues to happen I think I'll try running the wings in the "float" position. That should take all the pressure of both side cylinders. If uneven cylinder pressure is the cause that should resolve it.

I'll post an update once I know more.

Thanks again for all the help.

 

[kthompson]

I would suspect the fitting that is leaking was the source of the air in the hyd oil.
Was going to suggest you use the float position but the fact you have run this set up for good while with no issue so something has changed. Could you have a relief valve that needs adjusting or replacing? You might be able to use a hand held infrared thermometer to pick up the issue where there is a "hot" spot in the system. Have you checked all the coolers to be sure they are clean and again use the infrared thermometer to check for blockage.

 

[CoyPatton]

Does your tractor have a cooler on it for the hydraulic fluid. It would be somewhat similar to a truck’s transmission cooler. If equipped, is it clean? A product called radiator genie should still be available. There was a 2 wand set that one wand was designed for air and the other for water.

 

[Zebrafive]

If that was the suction line for the pump, that would be the source of the air into the system.

 

[wpchrist]

Thanks for the replies.

I regularly clean the cooler, and it was also cleaned by the John Dealer when the new pump was installed. They said it wasn't bad, so I'm not sure if that caused the initial problem leading to needing a new pump. Either way I'll look into the radiator genie suggested by CoyPatton. I think the initial problem may have been a sticking control valve as Texasmark mentioned above. I was hoping to get it back into service and try and do some more diagnostics watching all of these areas more closely. I like kthompson's idea of using a infrared heat gun to search for hot spots. I'll also try that if the overheat problem happens again. And I haven't thought of a relief valve. That's another avenue I can pursue once I'm back to the shop.



As for the air in the system, a loose fitting on the suction side would surely cause that, but I am thinking the leak was on a pressure side due to the force the fluid was coming out with when i started it an looked underneath. I checked the JD parts diagram and found the line and the o-ring, but its not easy to decipher if it's pressure or suction, but I'm pretty sure it goes to the valve spool in the brake lines, so that would confirm it's pressure. I think the air wasn't introduced from a leak, but rather from the removal and replacement of the hydraulic pump. Like maybe it was some residual air left in the system after that repair.

I'm picking up the seal from JD tomorrow and hope to have the repair done by Thursday or Friday. By that time there's going to be some mighty long grass to cut, so hopefully it goes well and I can start cutting Friday or Saturday, and see how it holds up.

I'll keep you posted as I learn more.

Thanks again for all the help.

And Zebrafive, I know it's in another thread but I haven't gotten back to that 5425 repair we talked about yet because of this breakdown, but as soon as I do I'll post a follow-up there.

 

[wpchrist]

Hydraulic Problems Solved. I thought I'd post the resolution in case it helps someone else with the same issues.

Steering: The system was indeed self-bleeding and the issue cleared up on its own.

Hydraulic overheating: As mentioned previously we had a new pump installed by the dealer. Unfortunately a hydraulic line was left loose during that repair causing a loss of all the fluid and another hydraulic overheat warning. I installed a new oring and reattached the line to the hydraulic pump. This appears to have stopped the leak and the hydraulic overheat warnings. I still am not sure what caused the original overheat warning. Hopefully it was a failing pump and not a different problem that led to the pump failure. I'd hate to get down the road a little and start having pump issues again. I'll be sure to keep a closer eye on the hydraulic system now.

Also, we now have new engine error codes appearing, but I'll post those in a new thread.

Thanks again to everyone for all the help and feedback in solving this.

 

[wpchrist]

Thanks Kevinskarl. It's a little scary to buy a manual like this without knowing the publisher or being able to look inside first.

Does anyone have experience with these manuals that could give some reviews?

 

[Dave M7040]

Thanks Kevinskarl. It's a little scary to buy a manual like this without knowing the publisher or being able to look inside first.

Does anyone have experience with these manuals that could give some reviews?

Real John Deere WSM's are the best in the business.

The one in the link even has JOHN DEERE misspelled as JHON DEERE.

I would stay away and go for the real one regardless of $

Dave M7040