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This E350... 460 engine? How many Fuel Tanks? As in One or Two Fuel Fillers on the side of the coach? Is it Carbureted or Fuel Injected?
My recall is that a 1987 would still be Carbureted and probably has only One Tank.
If what I said above is true, then there's a "run resistor" powering the fuel pump. Here's a diagram.
In the upper part of the diagram there's a ".75 Ohm Resistance Wire" between the Cutoff Relay and the Select Relay. This assumes a Two-Tank chassis, but the Resistance Wire would be there in a One-Tank also.
The Resistor is bypassed when the engine is being started, and reduces voltage to the pump while driving. Still, running on full system voltage shouldn't burn a pump out in HOURS let alone minutes.
Do you know if anybody's modified the wiring?
