Hi all.what a nice forum for machine owners.i join from turkey.quick cut to problem ec55c volvo oil heating so first question control valve block there is a oil return hose directly to the tank.is it suppose to run oil continuously?in the picture that is i think a safety return oil hose but running to tank without cooling continuously seems like a problem to me .oil overheating maybe because of this.thanks in advance
Yes it runs oil through there continuously…..it’s a hydraulic return line. It will be a low pressure return. Have you verified you have a heating problem? A temp gun can trace down a heating issue area pretty quick.
Yes i have heating problem over a year now.i think I am gonna get temp gun to check nex thing.but isnt the return line should pass trough oil radiator to cool oil.chech this pic please
The cooler is still return oil under low pressure. Your heat will be building from somewhere on the high pressure side, or lack of air flow through the cooler. Do you have any functions that seem weak or slow?
Yes.blade.and if i lift blase while lifting boom it makes a weird sound in th valves
I would question what the main relief and port reliefs are set at. As far as the return lines, there are return check vales for each return line These provide some backpressure to aid regeneration of cylinders and the check in the return direct to tank is set higher than the one to the cooler. This allows it to function as a cooler bypass in the event of cold oil or a plugged cooler. You could have an issue with the return direct to tank but there are a lot of other things than can cause an overheat. Is it only the hydraulics that get hot?
Only hydraulics get hot.i mean. Because of hydraulic gets hot engine overheats too since only engine fan to cool engine coolant and oil is one.air goes first though oil radiator then engine radiator so when hydraulic gets too hot engine radiator only has hot air thus engine overheats too.tomorrow i am gonna take the pump out to take to ankara for rebuilt.its already 9500 hours on it.and maybe control valve block too.if i find the problem i will summarize all topic as solved so it serves to next owners.thanks all for informations.
You said main relief.isnt variable piston pumps doesnt give flow at set pressure on the pump unlike gear pumps.so in the valve block it should be little higher then pump?and port reliefs?can u explain?