Hello, I have a Case 580E and we are having issues with hydraulic fluid getting hot after about a hour of use or so. It has good power, and fluid is new as is the filter. I have checked pressure relief valve and it looked good, Guage at the loader valve shows 2475psi. We have pretty much rebuilt the machine and that included re sealing the spool valves on the rear controls for back hoe. We are running correct fluid as well. At this point is it possible the pump? Relief valve bypassing? Spool valves bypassing? Or should we just add a auxiliary cooler/fan assembly? Any help would be appreciated.
It already has a cooler. Did you clean it ? You need to fix the cause and not add another fan or cooler. Are all the control levers returning all the way to the neutral position when they are released ?
Cooler is clean and fins are straight and clean. Valves are returning as they should.
How do you know its overheating? What has been checked as far a readable temps and how was that done?
Honestly just by touch, but you won't leave your hand on any of the rear cylinders for any amount of time. And it starts to lose power as temp climes. I can check temp with a temp gun.
Yeah, let's do that. Feel can be deceiving
I'll check it and get back. I'll guess fluid is 150 give or take. Any idea what normal operating temp is? I have manual but can't find it in there.
Operating temps will be between 180 and 210 depending on conditions
That's per Case?
Does the engine seem like it has a load on it when all the hydraulic valves are in neutral ? You say it loses power the hotter the oil gets. Just hydraulic power or is the engine losing power ? Is the hydraulic pump making any noise ? There is an outside chance the oil cooler is partially plugged internally.
No load when controls are centered, pump is quiet and it doesn't lose power per the engine rpm
Did you alter any of the circuit relief valves when you were working the spools ? Do you have the service manual ? Here is the page describing hot oil problems. Take notice of what is says about the oil cooler bypass spring.
I do fear my controls are not moving all the way into full position. The rod ends are kinda shot. Thank you for the information
Vega718, do you solve problem? I have for the same as you