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jd 710c hydraulic pressure loads up and engine stalls out
- Thread starter dwagidig
- Start date
Hydraulic pump stroke control valve, priority valve, an internal leak somewhere in the loader or backhoe valves.
Need to start by checking pump standby pressure, and flow if possible. You should have a constant pressure with near zero flow when not working the loader or hoe.
The pump always tries to put out enough oil to keep the pressure at like 2,500 psi, if there's a leak, or I think there's a main relief in the priority valve that could be opening at a lower pressure, the pump keeps pumping more and more oil to try to keep the pressure up. If it can't fill the hole pretty soon you've got maximum pump output going nowhere pulling the engine down.
If by chance someone has adjusted the pump pressure setting higher than the main relief, or the main relief is not holding pressure it's dumping oil over the relief.
That would be my guess.
Need to start by checking pump standby pressure, and flow if possible. You should have a constant pressure with near zero flow when not working the loader or hoe.
The pump always tries to put out enough oil to keep the pressure at like 2,500 psi, if there's a leak, or I think there's a main relief in the priority valve that could be opening at a lower pressure, the pump keeps pumping more and more oil to try to keep the pressure up. If it can't fill the hole pretty soon you've got maximum pump output going nowhere pulling the engine down.
If by chance someone has adjusted the pump pressure setting higher than the main relief, or the main relief is not holding pressure it's dumping oil over the relief.
That would be my guess.