JD 4640 ps hydraulic pump

[jd4620fwa]

need help diagnosing/troubleshooting problem on 4640 powershift. Upon startup we have to wait quite a while for hydraulic pressure to built for three point, hydraulics, pto, and clutch/transmission engagement. It has been getting worse over the past year to where we have to crank the rpms to get the pressure built up. Wondering which pump is causing it, changed both filters/screen to no avail. Heard there is a pump in back run off of a hex shaft that sends oil to the front pump??? thanks

 

[tim s]

Your 4640 power/shift has the trans. pump in back of the flywheel,no hex shaft,,check the sump screen and of course the trans. filters, if that's all good it most likely has a weak trans. pump, a total trans pressure check should be run first,,but it's probably a weak pump....