Ex350-3 LC

[Will-Power]

Hey all, just wondering if anyone has seen this before, customer says that when the machine heats up, one pump starts vibrating bad and making noise. I haven't seen it my self, I will tomorrow, so I can't be more specific. I am thinking there is a control issue that is causing problems or the pump is going down. They said the oil going into the pump was 212F so I would say it's running pretty hot. Does anyone have a schematic on the pump circuit they could send me?

Thanks

Will

 

[simonsrplant]

This may or may not be related... I've seen this on a few Hitachis...
There is a Jose going from the underside of the pumps to the frame of the machine. Goes no where and is blanked off. Almost seems pointless but fit an aftermarket hose or plug off and the machine will vibrate badly. May be worth a look if it's been replaced with an aftermarket hose assy.

 

[Tractorguy]

The hose he is referring to is an attenuator hose and it's to soak up any vibration the pump may cause. Could be the bearings for the gear train in the pump wearing out as well. Do any functions change?

 

[lantraxco]

Check the case drain if it has one, excess case pressure from internal leakage can cause the piston feet to lift off the swash plate.... Of course he's checked the suction strainer yeah?

 

[simonsrplant]

Thanks Mr Tractorguy... Been wondering about that!!!