Just to be on the safe side, take the pumps off. Take them apart. Then look at the parts TM, for the exploded view of the electric fuel pump. Compare the picture to the pump. Same amount of parts? Don't laugh. I have opened some up to find that the magnet is not there. Pump doesn't work very well without the magnet. Then put the whole mess in a can full of carb cleaner or some other liquid that will clean it up. Wait a day, reassemble. Then, hook up a hose to the input side, and a pressure meter if you have one, on the out put side. 6-7 PSI is what you want to see. If you do not have a meter, then put a hose on the output side and fill a liter container. Should not take more then 30-40 seconds, if that. A person could do worse then read the -12 TM, Maintenance of fuel system. Lots of good info there, and it applies to EVERY MEP and TQG gen set in the military system. If you think you are losing pressure someplace, remove all the hoses and put Teflon tape on the fittings, before putting the hoses back on. Toss the check valve into the carb cleaner also. Then that's about it for the fuel system.
Note: the electric fuel pumps require a very good ground. That's the reason they are SUPPOSED to have serrated washers under the mounting bolts. If by some chance you do not have them, you should get some. Normal washers and lock washers are not good enough. Often the water separator screen is missing. And the petcocks are missing or damaged. They are there for a reason. Use them. if you cant remember which wires go to the electric fuel pumps and the Aux, its easy. Place S1 in the run position. Two of the wire will be hot. They are the primary fuel pumps. The third one can only be AUX. As long as you have it all taken apart, remove, clean and test the AUX fuel solenoid. Better now, then when in the middle of the night you get this great idea to hook up an AUX fuel line and drain from another tank.
