New to the 2940 and have a hydraulic issue. Had a good day to squeeze in some plow work. After an hour or so, the steering got
choppy like the power part would come and go. Then I needed to raise the bucket at the fence and it chattered moving up and down.
When I got to the end of the next row, the rockshaft would barely come up out of the dirt. So I parked it and drained the hyd fluid
to check the sump screen(did not look at the filter). Had some partials but not much. The hyd fluid did have signs of water. Would
the water in the hyd fluid cause this or maybe a recirculating valve stuck open starving the implements of fluid power?

Any tip for checking pump pressure or to isolate the problem?
Bryan
 

Several things can cause hyd's to stop operating correctly & thorough diagnostics is the only way to determine the hyd problem. JD utility tractors with hyd systems similar to your tractor have a long history of the oil tubes that supply oil to hyd hi-lo & pto clutch failing. Water in hyd oil is not good as the water can cause brake & wet clutch linings utilized in hyd hi-lo & pto to fail. What type hyd valve controls frt end loader? With 3 pt raised,engine operating look in hyd filler hole behind seat for spraying oil which would indicate leaking RS control valve seals.
 

It has a JD 158 loader. Not sure on the manifold, but I will get a picture tonight and will look at in the filler cap for spraying.
thanks.

mvphoto47803.jpg
 

Also if it helps, I recently replaced the 8 hoses on the front of the loader for the cylinders. Preventive maintenance as they where pretty dry rotted.
 
My guess is transmission tube for starters and after that depends on how long it ran that way. A close up pic of the right side just above the filter at the case joint would help. If there's a set screw there it's got the updated tube. If not it will have.
 
(quoted from post at 12:40:24 01/14/20) New to the 2940 and have a hydraulic issue. Had a good day to squeeze in some plow work. After an hour or so, the steering got
choppy like the power part would come and go. Then I needed to raise the bucket at the fence and it chattered moving up and down.
When I got to the end of the next row, the rockshaft would barely come up out of the dirt. So I parked it and drained the hyd fluid
to check the sump screen(did not look at the filter). Had some partials but not much. The hyd fluid did have signs of water. Would
the water in the hyd fluid cause this or maybe a recirculating valve stuck open starving the implements of fluid power?

Any tip for checking pump pressure or to isolate the problem?
Bryan

Loader operated via a joystick or from both SCV outlets ?
We need to know what is found in the transmission oil filter. When taking the cover off the filter . Is there a hose connected to it or a bung to connect a hose to the filter cover ?
This would be the time to also check the Ph and corrosion inhibitors in the engine coolant . JD dealerships etc stock a test kit.
 

It appears the FEL control valve hoses are attached to tractor correctly. I think your FEL control valve is a closed center only type not the convertible to open center type. Does extra hose teed into hyd filter cover go up to scv?
 
One important thing to do first is change the paper hydraulic filter. No need to drain tranny. The paper has swell due to the water ingression and will not let oil go trough. That issue is also very common with diesel fuel. Filters.
 

I haven't tried it yet, but your saying I can drop the hyd filter bowl and it will not drain all 15 gallons like through the drain plug?
 
(quoted from post at 18:39:31 01/15/20)
I haven't tried it yet, but your saying I can drop the hyd filter bowl and it will not drain all 15 gallons like through the drain plug?

The filter is it's own compartment isolated from the main case . The filter receives approx 175psi oil sourced from the transmission sump via the transmission oil pump.
That pumped oil plus what oil is being returned from the loader is forced through the filter.
After the priority items in the transmission are lubricated or clutches/brakes are pressurized to approx 145-165psi. All remaking oil is routed to the front pump. What oil is not used by the front pump flows through the cooler, a reserve tank and back to the transmission case.
If high demand hydraulic devices such as loaders, hydraulic motors, backhoes etc are used and the oil is just returned directly to the transmission sump. The front pump will starve as the rear pump can not keep with constant high demand loads.
 

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