alchemysa
Veteran Member
Before I can get back to my B1550 HSD (300ks away) and do some servicing, I'm looking through the diagrams in the parts manual to see what goes where. One thing slightly confusing me is the route of the hydraulic oil. Can you guys tell me if I've got this right. Ignoring the FEL, the route of the basic tractor hydraulic oil flow is Oil Pump>Distribution block>3pt hitch valve >Rear Diff. From the Rear diff it flows via gravity to the transmission case then through a short pipe to the HSD unit. It is then sucked from the HSD back to the oil pump (via the oil cooler), or alternatively its sucked directly to the oil pump from the transmission case. (I see there are screw-in screens on both sides of the transmission case).
Can you tell me if I'm on the right track here. I guess this would be a common layout in other models too. It just seems puzzling that the only way cooled oil can get back to the transmission assembly to keep the HSD etc topped up is the long way, via the 3pt hitch valve etc. I can't see any other pipes returning oil to the Diff/Gear/Trans assembly but maybe I'm overlooking something obvious. It wouldnt be the first time.
Regards David
Can you tell me if I'm on the right track here. I guess this would be a common layout in other models too. It just seems puzzling that the only way cooled oil can get back to the transmission assembly to keep the HSD etc topped up is the long way, via the 3pt hitch valve etc. I can't see any other pipes returning oil to the Diff/Gear/Trans assembly but maybe I'm overlooking something obvious. It wouldnt be the first time.
Regards David
