ydraulics:
Type: open center
Pressure: 2550 psi [175.8 bar]
Valves: 1 to 3
Total flow: 7.7 gpm [29.1 lpm]
15.3 gpm [57.9 lpm] (tandem)
Steering flow: 7.7 gpm [29.1 lpm]
Steering press.: 1500 psi [103.4 bar]
Install a 3000 psi pressure gage and check the pressure.
So you are saying that the 3pt works and the loader does not work.
Does that include both lift and curl.
There is one problem that I can think of that will allow the 3pt to work and the lift will not, and that is the nut that secures the cyl piston. If that nut comes off, the fluid will just recirculate through the cyl and no action will occur.
If you install the gage in a tee in the IN port of the FEL valve, you can see any pressure developed by any component in the hyd system. , and then, if you raise the 3pt to max, and you show about 2500 psi, then you know the pump is working good.
The loader valve can have several problems.
Is the FEL valve lever operated or cable operated?
You mentioned the hex plugs between the work ports. Those are load check valves, and they can fail, so check them out before tearing the valve.
The relief valve can be stuck open as someone mentioned, and fluid will pass on to tank.
The relief valve is the large tall hex capped relief valve close by the IN port or the valve.
Remove t and inspect, clean or repair or replace.
You will need to reset the FEL relief to about 2550 psi
Not all valves have o-rings that you can replace. Those o-rings are primarily there to keep dirt out, and they are not high pressure seals. If you don't have external leaks, don't mess with them.
Do the simple test first before messing with the valve.
Your valve is not stuck in the float position is it.
Is your spool moving in and out the valve equally. The float position will have a little more travel than the retract.
Holy cow J J, that is a lot of information and a lot of it is going over my head, but I will do my best to respond to your questions.
- Yes, the 3pt works but the loader does not lift or curl. Nothing from FEL is working, but there is no apparent strain on the system, no leaks anywhere. It worked fine to lift the bucket when I started the tractor, but then when I got to the field and tried to raise it higher nothing would raise anymore.
- "the nut that secures the cyl piston" I don't know what you mean here. Are you talking about a nut on one of the hydraulic cylinders for the FEL? Is there a cylinder piston somewhere else? I would check this, but I have no idea what you mean.
- "Is the FEL valve lever operated or cable operated?" THere are two levers on the FEL valve. One raises and lowers the loader arms, and the other raises and dumps the bucket.
- Load check valves are under those hex plugs that I thought nmight be to bleed the system. Got. I will check those for crud when I clean out the rest of the valve.
- Relief valve will be cleaned as per both your and ssdoxie's suggestions. I don't know how to set the relief to about 2550 psi, but hopefully that will be apparent when I take it out. Are there markings on it that indicate the psi?
- There are no external leaks, so maybe the o-rings are fine then. Hopefully a cleanup will do the job.
- Not sure what you mean by the float position, but both of the levers are moving in and out of the valve and do not seem any different from how they were in the past.
I do not have a pressure test guage nor do I know anyone who might have one to lend me. I am at least an hour from the nearest hydraulic supply store, so I think my best way to start is to clean out all of the stuff you guys have recommended. If that doesn't work I will look into renting a pressure guage and do as you suggested to confirm if the pump is working properly.
Thank you for the detailed response, much appreciated.