White 2 105 hydraulic oil overheating

Hi Everyone  I am a new member and apologize if this topic is one that has already been dealt with on this forum. I am still trying to find my way around. Is there a way to search and veiw old topics without having to scroll through them all?  we have a White 2-105 (no 3 pt) that overheats the hydraulic oil after running for short time. Otherwise hydraulics function fine. No problem lifting equipment. I have checked the pressure relief valve and compensating valves and all seems fine. Installed pressure gage and set to aprox 2100 psi, pressure relief at about 2500 psi. From looking on line and using an IT service manual it looks like there is a seperate inner pump for hydraulic oil cooling and transmission lube. I removed the line going to the cooler and am not getting any flow to the cooler. There seems to be fluid available to pump as good flow comes out of the little bleed valve. Any

info on exactly how this system works and how to test it would be greatly appreciated.   Thanks

White 2 105 hydraulic oil overheating