When the one way flow ( Green button ) is lit, the flow of oil back from the attachment is supposed to go an easier route back to the cooler and tank. As in, the fluid does not have to go back through the spool valve. The solenoid operated valve is centerline between the cab and right over the engine. My question is , can anyone tell me if they run in detent ( yellow light) and one way ( green light) at the same time so to reduce oil temp while using , say a mower or road broom? Thanks, I am new to this forum. I sold my Cat dozer with Brown tree cutter and now have a Takeuchi TL140. The adventure begins! Jim ( Belzona Guy) Pedro, Ohio PS, I have shop manual and early parts manual for free if it will help anyone. I can e mail them as pdf files.