JDirt
Well-Known Member
I have an excavator that is giving me fits, maybe someone can help me out.
I have rebuilt the main control valve and the electric solenoid valve block. Put it back in, and I seem to have flow, but my pressure won't come up. All actuators work with a light load, but it doesn't have any hydraulic power. Won't lift itself up, won't dig much, won't track up a hill. Before the rebuild, the machine would lift itself up, dig, etc.
So I put a gauge on the main pump. Every function to relief is 2600-3000 psi. Book says 5000-5250.
So I try adjusting the main relief valve, I had it out when I rebuilt the valve stack, so I thought it might be out of adjustment. I've turned it both directions several turns, no change. At about 5 turns in, it got tight, like it bottomed out, still no change. I turned the overload relief for the bucket down a few turns and relief for that function dropped below the rest.
I don't think it's electrical, because I can unplug the swash control solenoids and put the pump full bore, and I still never see more than 3000 psi from the pump. The only difference is with the solenoids plugged in normally, the machine just seems to go to relief @ 3000 on the gauge. When they are unplugged, same reading, but kills the engine. Am I right in saying this eliminates any electrical problem?
I have checked for trouble codes, and get 35, which is arm bottom pressure sensor fault. The troubleshooting manual says the symptoms of this is poor combined operation. That doesn't sound related, and I think I've had that code since I've had the machine, without ill effects.
I have put in a new dp sensor, adjusted it and the angle sensor to specs. I've also replaced the wiring to the right rear of the machine.
So, does this sound like the relief valve took a dump? It's $550 from Deere, unless someone knows another place to get one. Or is there another possibility?
I have rebuilt the main control valve and the electric solenoid valve block. Put it back in, and I seem to have flow, but my pressure won't come up. All actuators work with a light load, but it doesn't have any hydraulic power. Won't lift itself up, won't dig much, won't track up a hill. Before the rebuild, the machine would lift itself up, dig, etc.
So I put a gauge on the main pump. Every function to relief is 2600-3000 psi. Book says 5000-5250.
So I try adjusting the main relief valve, I had it out when I rebuilt the valve stack, so I thought it might be out of adjustment. I've turned it both directions several turns, no change. At about 5 turns in, it got tight, like it bottomed out, still no change. I turned the overload relief for the bucket down a few turns and relief for that function dropped below the rest.
I don't think it's electrical, because I can unplug the swash control solenoids and put the pump full bore, and I still never see more than 3000 psi from the pump. The only difference is with the solenoids plugged in normally, the machine just seems to go to relief @ 3000 on the gauge. When they are unplugged, same reading, but kills the engine. Am I right in saying this eliminates any electrical problem?
I have checked for trouble codes, and get 35, which is arm bottom pressure sensor fault. The troubleshooting manual says the symptoms of this is poor combined operation. That doesn't sound related, and I think I've had that code since I've had the machine, without ill effects.
I have put in a new dp sensor, adjusted it and the angle sensor to specs. I've also replaced the wiring to the right rear of the machine.
So, does this sound like the relief valve took a dump? It's $550 from Deere, unless someone knows another place to get one. Or is there another possibility?