HOW TO INSTALL FUEL FLOW TRANSDUCER 201B IN AIRCRAFT?
This question comes up often enough so we decided to write on how best to install the fuel flow transducer model 201B manufactured by J.P. Instruments in an aircraft. Orientation of the 201B fuel flow transducer: To start off and assuming you have removed the existing fuel flow transducer, hold up the new 201B fuel flow transducer in a horizontal position with the three wires up – because this is exactly how it is to be fitted. Fitting the fuel flow transducer any other way will lead to its failure. When the fuel flow transducer is in the horizontal position, the rotor within it are proper oriented and aligned with fuel flow. This is how it is meant to operate. Also, while fitting it, be sure that there is no bend closer than 6 inches either in the inlet or outlet pipe i.e. no bends before or after the transducer. Also, do not use aluminium or brass fittings when installing the 201B fuel flow transducer – use only AN816-7 Steel. The transducer is engineered to seal tight so do not use Teflon tape, or other thread sealant compound of any kind. Also, the transducer is marked IN and OUT for the fuel lines – so make sure you attach it correctly or the rotor will malfunction. The maximum torque should not exceed 15 ft lb (180 lbs.) or roughly, two full turns past hand tight.