when I attach gauge to each FEL port pressure goes up to 2500 psi. when I let go over the joystick, all the pressure bleeds out. is it supposed to do that or maintain pressure? the electric scv in the rear holds pressure steady at 2500 psi if I let go of the switch
question about checking Fel hydraulic pressure on 3320
- Thread starter FatSlob
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J_J
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If your hyd system is open center, and you have the gage in a tee in the IN port of the tractor, you will see the pressure for any hyd component using fluid.
If the SCV is de-energized, you should read 0 to low pressure.
If your hyd system is CC, then you will have pressure at the IN port of all valves, or you will have the standby pressure.
If you operate a cyl or cylinders, you will read the pressure developed by the load.
If you are reading 2500 psi, then something is using the hyd.
If the SCV is de-energized, you should read 0 to low pressure.
If your hyd system is CC, then you will have pressure at the IN port of all valves, or you will have the standby pressure.
If you operate a cyl or cylinders, you will read the pressure developed by the load.
If you are reading 2500 psi, then something is using the hyd.
Using no tee in line. Just a liquid filled gauge with a 12 inch section hose with a male quick connect. I undid all the loader lines from the 4 quick connects at the tractor so I could check pressure at each port. Pressure goes up at same rate and drops off at same rate at each port. I also checked the 2. Lines at the rear. The rear holds pressure but each line that uses the loader joystick does not hold pressure. I'm pretty sure 2500 psi is the normal working load each port should have. That's not the problem. Just curious if the lines are supposed to hold pressure when you let go of the stick. Mine is not holding pressure
J_J
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It is possible to pressurize the lines.
It will bleed off if you wiggle the joystick or the lever for the 3pt.
You only develop pressure when the cyl are doing work. or you deadhead the hyd system.
The valve spools are designed to shut off the fluid to the cyl, however, if there is a load on the cyl, you will have pressure.
Without having to plug into QD's to test hyd pressure, why not permanently mount the gage in the IN port of the first valve . You could even install a male QD to plug the gage into..
That way, you can monitor and trouble shoot the hyd system.
Any hyd action you do will be reflected on the gage.
It will bleed off if you wiggle the joystick or the lever for the 3pt.
You only develop pressure when the cyl are doing work. or you deadhead the hyd system.
The valve spools are designed to shut off the fluid to the cyl, however, if there is a load on the cyl, you will have pressure.
Without having to plug into QD's to test hyd pressure, why not permanently mount the gage in the IN port of the first valve . You could even install a male QD to plug the gage into..
That way, you can monitor and trouble shoot the hyd system.
Any hyd action you do will be reflected on the gage.
Here's whatis it doing. When the pressure bleeds out, I'm not touching the loader joystick
Psi - YouTube
Psi - YouTube
arlen4720
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The pressure is going to disappear pretty fast... There is nothing to "store" the pressure (except for the elasticity of the hose going to your gauge), so all it takes is 1 fraction of a fraction of fluid volume to leak back through the valve, and the pressure is gone.
The rear electric SCV does have some check valves in there, and the valve might just be better sealing, but I bet if you wait a little while the pressure will go away there too.
operating pressure at each loader port is supposed to be at 2500 psi. Mine will go up to 2600 psi and then slowly go down to 2500 psi when I open up a valve. is this normal?
Trying to track a issue of where the loader will studder while raising and driving the ehydro at the same time. and while it is studdering, you will hear a sound like you would if it is low on hydro fluid. Im topped off with hydro fluidhowever. I have fresh fluid and filters. achine always done this
Trying to track a issue of where the loader will studder while raising and driving the ehydro at the same time. and while it is studdering, you will hear a sound like you would if it is low on hydro fluid. Im topped off with hydro fluidhowever. I have fresh fluid and filters. achine always done this
arlen4720
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The pressure sounds normal to me.
I'm not overly familiar with the 3x20 hydraulics, but i think they are close to the 4x20's...just smaller.
There is a separate hydro pump for the implement (loader, 3 point, scv's), a separate pump for the power steering, which also supplies the hydrostatic drive loop with "charge flow" (makeup oil).
And of course a separate piston pump for the hydrostatic tranny.
Does the fluid appear to be aerating? That is one thing that will affect all of the 3 hydraulic systems since it is a common sump.
I'm not overly familiar with the 3x20 hydraulics, but i think they are close to the 4x20's...just smaller.
There is a separate hydro pump for the implement (loader, 3 point, scv's), a separate pump for the power steering, which also supplies the hydrostatic drive loop with "charge flow" (makeup oil).
And of course a separate piston pump for the hydrostatic tranny.
Does the fluid appear to be aerating? That is one thing that will affect all of the 3 hydraulic systems since it is a common sump.
Thank you for reply. I have no good way to see if the oil is aerating on this machine. Can't see in the fill hole. When the issue happens, the steering works fine and the e hydro works fine. Just the loader controls makes the sound and stutters