you could be right, here is how to check. remove the return rubber line from the top of the pump, has a red clamp on it. remove the fitting 9/16 i think. look at whats inside of it. blow it backwards with air and see what comes out. should be just fuel. re install it, crank the motor, should see a good stream of fuel come out. if you dont, no fuel to the pump, (5 psi) if you have trash in the check valve, your pump is coming apart inside. rebuild it. 84 models had bad flex rings that would come apart. even bad pump should run after this procedure. if this truck just made a 2200 trip i doubt pump just quit. something else going on. i have seen it all!!
i dont recommend doing this but i was in las cruces,nm one time with a stopped up injection pump in a m1010 ambulance with less than 10k miles, i gutted the check ball out of the return fitting and drove the rest of the way home, to austin,tx