Case 430 skidsteer low charge pressure

Got a problem I can't figure out. Machine was pushing fine then suddenly sort of locked up.The charge pressure light came on.So I checked charge pressure at the port and get about 50psi at idle (should be 360) Checked relief valve for broken spring all looked good. Pulled pumps out and checked charge pump.From what I can see nothing broken that would lead to instant failure like happened. So my question is can the charge pressure be lost in another way ( all the circuit relief valves look fine) At wits end when cant find anything broken

Can anybody help me with this?

Charge pressure fills the hydrostat loops at all times, keeps the low side full when actually travelling, and makes up lost oil that escapes the loops due to internal bypass in the pumps and the motors. In addition usually motors have some type of "flushing" system whereby a metered amount of oil escapes into the motor case and drains out to the cooler, the cool oil from the tank being pushed into the loop by the charge pump keeps the entire system cool.

So, piston pump failure, motor failure, flushing system failure. I am not familiar with the Case 430 so I can't point to anything specific, sorry.

Thanks for the reply. Unfortunately my problem is that the charge pump is only reading about 50psi (reading at outlet of pump) and I cant find anything wrong with it.When the machine stopped all of a sudden I expected to find something broken spring or drive but nothing so I'm a bit stuck

jonno said:

Thanks for the reply. Unfortunately my problem is that the charge pump is only reading about 50psi (reading at outlet of pump) and I cant find anything wrong with it.When the machine stopped all of a sudden I expected to find something broken spring or drive but nothing so I'm a bit stuck

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You have leakage in the loop or the pump is bad. A case drain test would be next in line.

What's the serial number

have you checked your other pressure? main relief and pilot if this is a pilot machine? with out a serial its hard to say case liked changing sytems. charge pressure is internal to drive pumps its a gear pump. pilot pressure is the pump furthest from the engine. you took the internal gear pump out and checked it? you will see wear on a gear pump. check hyd filter for metal

Did the engine to pump coupler strip out?