IF your HR has the Roadmaster chassis. The pick up tube system is separate from the Fuel gauge sending unit. The fuel gauge sending unit on a Roadmaster can be calibrated. But the odds are it is defective given its age. Depending on the model Roadmaster, you can have 2 adjustment pots. One for the main fuel gauge and one for the APU level for the dash indication on the gauge. NO APU (genset) has any type control that will KNOW when the fuel level is low and not run or pull fuel. It will run the fuel pump regardless of the fuel level or any indication. The Fuel sender unit on a Roadmaster is very easy to replace and the tank does not have to be dropped to do like on a Frtliner chassis. You just have to calibrate it once it is replaced. Monaco will be where you get the sending unit. Doug
