I have a Mitsubishi bd2g dozer was pushing brush hydraulics stopped working checked fluid was milky let it set a couple of hours dozer starts up hydraulics start then stop I changed fluid and filter tried again same issue hydraulics work for a few minutes then stop what could be the problem
I'd start with the suction side of the hydraulic pump, it could be sucking air, it could have water that causes foaming in it's own ways. Are you sure there's not a suction screen in the tank that could be plugged up? Is there any rubber hoses, or seals that could be leaking air?