Hydraulics partially not working at high RPM

[Harry in Ky]

The photo is old and at that moment i missed a fitting. Now the 3 lines are connected to the valve. I do have a spécial fitting for the Carry over, which i bought with the valve. The cylinders which go up and down are single acting. The "thing" in the valve was changed for a simple acting one.
It is the one on the valve. It has a little orange cap on the photo.
Thanks for your help.

Sorry but as I see it the "thing" in the valve with an orange cap is a relief valve adjustment. It has nothing to do with single acting cylinders. If the valve is now plumbed as your diagram shows, and the supply line from the pump goes to the loader valve first, with nothing between the pump and the valve, then the problem has to be either the valve or the pump. I think you need to revisit the valve and that work port with the plug in it.

Next question. The loader doesn't work when the engine revs are raised. Is that both loader functions or just the raise and lower?

 

[Th french mechanic]

Sorry but as I see it the "thing" in the valve with an orange cap is a relief valve adjustment. It has nothing to do with single acting cylinders. If the valve is now plumbed as your diagram shows, and the supply line from the pump goes to the loader valve first, with nothing between the pump and the valve, then the problem has to be either the valve or the pump. I think you need to revisit the valve and that work port with the plug in it.

Next question. The loader doesn't work when the engine revs are raised. Is that both loader functions or just the raise and lower?

To convert it from double to single acting, I changed that

The pressure relief valve was adjusted last week with a pressure gauge. The 3-point lift works perfectly, and according to my calculations, the flow is correct at low rpm (I don't know about high rpm), and the pressure is correct. Before digging in the valve, I'll test the quick couplers and see what's going on about pressure and flow when I increase the revs. I'll do that on Saturday and will tell you the results
I think both do not work, I'll test that again and take a video.
Have a good day

 

[Th french mechanic]

Hello
I've attached my trailer to the tractor and tested the hydraulic dump, the problem is the same, after 1200 rpms it stops flowing.
I think the only thing left to do is replace the old pump with a new bigger one.
I've seen some kits on the internet. If you're experienced with ford 3000's hydraulic pump replacement please share your experience.
Bye

 

[zzvyb6]

Oil supply line crimped or collapsed ? Try removing the cylinder connections and drain their flow into a bucket just to see if it's supply, volume, or some other flow restriction in the system. Sounds like the pump is starved for fluid. I also saw this symptom on my 4000 and a Kubota caused by use of high viscosity oil. Switched to JD Hyguard-Low Vis (ISO 32) and problems disappeared. Had to drain the cylinders, too. Most oils are between 46 & 68 viscosity rating.

 

[Th french mechanic]

Hi
THe oil is Fuchs agrifarm utto mp AGRIFARM UTTO MP | Automotive lubricants | FUCHS LUBRIFIANT FRANCE S.A.
The pipes aren't damaged. The suction filter seemed ok when I disassembled the lift.

 

[Th french mechanic]

The oil specs are :
Density at 15 °C DIN 51757 0.880 g/ml
SAE Grade SAE J300 10W-30 SAE J306 75W-80
Kinematic viscosity 40°C DIN 51562-1 64 mm²/s
Kinematic viscosity 100°C DIN 51562-1 9.54 mm²/s
Viscosity Index DIN ISO 2909 130
Pour Point DIN ISO 3016 -42 °C
Product dyeing DIN 10964 none
Is 130 the number supposed to be between 49 and 68?

 

[oldnslo]

Hello
I've attached my trailer to the tractor and tested the hydraulic dump, the problem is the same, after 1200 rpms it stops flowing.
I think the only thing left to do is replace the old pump with a new bigger one.
I've seen some kits on the internet. If you're experienced with ford 3000's hydraulic pump replacement please share your experience.
Bye

If the lift (3 point) is working it probably is not the pump since same pump supplies flow to both circuits.

You state flow stops at 1200 RPM. Does pressure also drop at this time?

 

[Th french mechanic]

If the lift (3 point) is working it probably is not the pump since same pump supplies flow to both circuits.

You state flow stops at 1200 RPM. Does pressure also drop at this time?

Last week it was colder, and the lift seemed to be working ok.
But yesterday, it was warmer the lift stopped working above 1200 Rpm, as my trailer lift cylinder and as the loader.
I will borrow the flow and pressure measurement tool to my mechanic on Saturday.

 

[jigs_n_fixtures]

Sound like: a collapsing inlet line to the pump; or, an air leak on the suction side; or, something floating in the reservoir which lifts up and blocks the inlet as the flow increases. Most probably something happening before the fluid gets to the pump.

 

[aircommuter]

First thing is I am believer in analytical diagnosis. But since I can’t do that in the internet I just going to throw out a guess.
Maybe a hose with a torn lining that acts like a flap when the oil flow speeds up.