Where do we go from here

[SVcummins]

Been thinking of looking into the pressure control valve and the oil cooler valve can’t remember what it’s called. Also could it have anything to do with the bearing thats out in the pto on the front of the transmission . For those who need an update the problem i am chasing is running out of oil when operating the front front end loader

 

[miangus]

Maybe disconnect the line feeding the oil cooler/reservoir and measure the flow with the engine at an idle. This would isolate to trans pump system if the flow is inadequate. Maybe trans pump relief valve is partially open. If the flow is adequate I would expect a high pressure leak is causing your issue.

 

[WTW]

If this tractor is a Power Shift Transmission?? Have you removed the return "rear hydraulic filter" and filter bypass valve assembly from back of filter compartment to inspect the filter by pass valve is not stuck open with debris caught in valve. If this valve is caught open all return oil from loader is dumped to sump. This tractor hydraulic system will not function correctly on charge pump oil supply only, it has to have its functional return oil or system will operate 25%. capacity. DW

 

[SVcummins]

Tractor is a sychrO new transmission pump installed doesn’t have 20 hours on it pickup screen clean filter clean loader plumbed in to a Separate valve off the rock shaft supply line return oil from valve plumbed into rock shaft drain

 

[WTW]

Is this a late or early 4020? Either way, to rule out leaks in rear Rock-shaft and SCV's if it is a late model tractor, for testing only plumb loader supply directly to pressure control valve outlet that supplies the rear of tractor to isolate / block off rock-shaft pressure circuits. If loader still does not function correctly, then leave supply plumbed direct and then plumb loader return directly to functional return circuit blocking possible leak in rear / rock-shaft return circuit. This will give us some direction whether it works or not. Let us know what you learn. DW