Hello Mr. Tore and Maciek,
The fuel transfer that I want to document would be from internal fuel storage tank like 1 IB. The reason for my interest is that when schnorchelling the cooling water pressure head to/from the internal fuel tanks is too high for the gravity tanks (14 mwc). So a directive was issued that when schnorchelling only the saddle tanks may be used as a fuel source to the gravity tank.
During the late war period, U-Boats with schnorchels were pretty much below the surface bound. Therefore, a fuel oil saddle tank low situation may exist, and then a the need to transfer fuel oil to the saddle tanks.
On Plan 9, internal tank 1 IB has a hose connection "b3" where the source is the internal storage tank 1 IB. If there was a hose connection between "b3" and "c" at the Auxiliary lubricating oil pump head, then could the pump transfer fuel through the tank selection valve chest and then to the saddle tanks? The cooling water pressure head already exists for the internal storage tank, and it's always available to the saddle tanks. It looks to me like this would be sort of a refueling situation for the saddle tanks, and the cooling water in the saddle tanks would be forced to exit at the header tank overflow...
Does this drawing look OK?
Regards,
Don_