Powerpack Question

• Check the non-return valve fitted between whatever is producing the pressure and whatever the pressure indication is coming from, for it looks like it is letting by.
• Check also the kick-in and kick-out points on whatever is producing the pressure.

Chances are, it will be one or both of them.

You didn't say if the pressure valve was an unloading valve or a standard pressure reducing. Under normal circumstances a system with an accumulator will have a un loading valve in the system. The check valves wear and begin to leak back causing the loss of pressure. The unloader then kicks in and pressure then is increased to set point. Check these items and see. Other wise consult a hydraulics person to help you.

Fixit

thank u fixit , same think I am suspecting , but by trial and error method only we can conclude i.e by replacing it with new unloading valve . is there any better way to clarify Regards Nithin

What would be the difference between pressure reducing and unloading valve.

When you say There is no External Circuit Leak, do you also mean there is no oil being supplied to equipment? If there is, that's where the oil is going.