Has any body ever seen this problem. We have a Kalmar DC845 RS5 that keeps losing brake pressure, the brake pump is at its specified pressure and getting red hot it seems to be stalling the oil at the brake charge valve which we have replaced, the pump has also been replaced. Accumulators are upto and holding the gas pressure.

The machine will run perfect sometimes for days then other days will fail within hours

We have the following pressures
174 Bar output at the charge valve
80 bar Gas @ Accumulators
Charging at 142 - 174 Bar over 2 mins +