B2400 hydraulic problem

[taftalw]

All hydraulics on my B2400HST are unresponsive except power steering after transporting. I have a trencher and backfill blade on this tractor and the 3 pt is restricted from movement normally but it can be raised alittle without bending support bars. That being said I can say that the 3 pt hydraulics are dead as well as the aux hydraulics that go to the backfill blade up front. Maybe its coinsidental but when I loaded all seemed fine as I raised the blade to load and lowered to deck before securing. Two hudred miles later and I cant get it off the trailer.

 

[J_J]

Check all the QD's if you have them. Do you live in a low temp climate? Can you tell if the pump is running? Do you have a pressure gage? Is the fluid level correct?

 

[taftalw]

I'm in S Carolina and I had cranked the tractor and let it run for maybe ten minutes. Correct me if I'm wrong but I think the power steering is developed at the same pump. All quick connects appear fine no leaks or drips. Fluid level is fine and oil looks clean on the dip stick. Power steering works effortless. and I do not have a gauge. I've got them on parts book on CD and the owners manual but will have to retrieve them tomorrow. Thanks.

 

[taftalw]

First check was for restrictions at suction revealed flow to be unobstructed. Second check was to confirm flow at flow divider mounted to top of pump, revealed some particulate lodged in spring. Particulate seemed to be possibly rubber or maybe gasket material but not enough to result in total loss of response. Power divider split output from power steering and rest of system. I then left out the internals of the divider and replaced the cap leaving it loose enough that I thought fluid, at pressure, would escape to some degree and started engine. The momentary run of engine proved only that there was sufficient pressure on cap to provide resistance in turning but I did not let the engine to run long enough for fluid to seep at threads as I did not know what damage might occur as a result of internals being absent from divider. I was able to detect that sufficient pressure was available to confirm flow to the power steering. This leaves only the possibility of a restriction in the 12 to eighteen inches of tubing between the power divider and the block mounted to the frame where the output is split to the two auxiliary valves that are inoperative and the rest of the factory installed system that are also affected or in the immidiate vicinity of the tubing connectors. Without knowing what pressures are required to operate the power steering and yet fail to show any signs of pressure at the other devices this is all I can conclude. This has proven to be the tedious task that I suspected it would be and why I elected to post for the world to see. Had this been a machine from the seventies where the roadmap of tubing is not made such a mystery by confines of sheet metal and magnitude of linkages all crammed into what is the compact tractor of today. Couple that with the fact that greasy knuckle busting mechanicing sucks no matter what color paint is on the hood. I'll have breakfast and continue.

 

[Egon]

mystery by confines of sheet metal and magnitude of linkages all crammed into what is the compact tractor of today.

Sometimes it's easier to remove stuff than try and work around it.

 

[J_J]

When there are two units using the same hydraulics, and only one pump, such as the PS, and the rest of the system, there is a valve to shift the fluid to the priority circuit when needed. This could be something like a shuttle valve. It might work like this. when you are steering, the fluid is shifted to the PS circuit, and the the cylinder operates. when you are through steering, the fluid is shifted to the normal tractor hydraulics. However, if the shuttle valve hangs up or is jammed in the PS mode, then you would not have any fluid in the other circuit, and all the fluid would go to the steering and back to tank.

Can you determine if there is a shuttle valve or divider valve, and determine if the fluid is being shifted when the PS mode is not being used?

The fluid from the pump has to be going somewhere, and if the PS is not activated, and none of the other hyd are working, then it would seem logical that the fluid is diverted from the normal flow, and and sent back to tank.

I think I would take the diverter/shuttle valve apart and clean or inspect it for any debris or galling.

If there was any blockage, then the relief valve might activate, and that is why I think the diverter/shuttle valve is not function properly.