Hello I have a gehl 6625 with a problem when running the engine at full throttle I lose hydraulic power, traction power is still good. If I bring engine back to idle hydraulics come back.
check the oil level in the tank, the suction line to the gear pump, and the suction strainer for clogging. Other than that, how cold is it and what oil are you using? Puzzling. Remotely possible the inner liner in the suction hose has come loose and is sucking closed?
Pump drive slipping under full power?
Doesn't the hydraulic pump run off the back of the drive pumps?
Yes the hyd. Pump is powered off the back of the drive pump. I just pulled the pump, the coupler for the pump and both corresponding shafts look perfect. It has 20wt. Oil in it and the outside temperature is around 70 degrees. I have pulled and checked all check valves in the self leveling valve and temporarily eliminated the safety control solenoids. I have not yet pulled the suction screen as I believed if the traction had power the suction was probably ok.
Traction is closed loop, so it doesn't need much oil to keep the loop full, and it should have it's own charge pumps. I don't know enough about the rest of the hydraulic system to hazard a guess beyond that.
I have the exact same problem with my 6625. When I rev more than 30-40% I loose lifting hydraulics, but drive still works fine. Did you find the cause?
Sounds like it could be a suction issue for the implement hydraulics. I have a different brand of skid steer but the implement hydraulics and drive have separate suction screens in the reservoir.
I'm having the exact same issue on my 5640e w/Deutz Would love to know if you have figured it out.