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Howdy folks! I have started this thread for Jeff, to get him started out on the right foot. I will walk him through how to do it a bit later.
I am new to the forum. I have an MEP 803 which works fine, EXCEPT the aux fuel pump won't run. I have followed the above suggestions, it still doesn't pump. I have replaced the aux fuel pump, also a new float switch which shuts the gen down when the bottom float is down, THIS part work.s, BUT with the bottom float up, the gen runs fine, and if I move the upper float down, there is 21.5 volts delivered to the pump. Apparently the aux pump needs at least 24 volts to run. I am doing these tests with the tank full and with the float switch outside the gen plugged into the appropriate connector. I don't believe that should matter, since the bottom float tells the electronics the tank is not empty and the upper float tells the electronics in its down position that the tank needs the aux pump to run. I have studied the wiring diagram and schematic for hours and I was Navy Electrician so I know up to a point how to read the schematics. I get lost in the complexity of the relays interactions, and the fault indicator module, since the fault indication module seems to be involved when the aux pump should run. There are NO warning lamps except when I make the low fuel float at the bottom position, then the fault lamp no fuel comes on. Also the connectors with the screw bottoms in the rear panel, do I screw them out with the twisty idem at the bottom of the plug, or do I simply rotate the twists screw then a quarter or half turn then pull up. I don't want to assume I am disconnecting the jacks right and mess them up. So I don't pull them too hard. I want to see if all that is going on is a loose connection, or high resistance connection, or a bad relay, or module. I need pin out readings on what voltages to read on S1, and the relays to trouble shoot this. I have and have read the manuals, not enough info on this specific problem. Any ideas would be much appreciated !! Thanks, Jeff
I am new to the forum. I have an MEP 803 which works fine, EXCEPT the aux fuel pump won't run. I have followed the above suggestions, it still doesn't pump. I have replaced the aux fuel pump, also a new float switch which shuts the gen down when the bottom float is down, THIS part work.s, BUT with the bottom float up, the gen runs fine, and if I move the upper float down, there is 21.5 volts delivered to the pump. Apparently the aux pump needs at least 24 volts to run. I am doing these tests with the tank full and with the float switch outside the gen plugged into the appropriate connector. I don't believe that should matter, since the bottom float tells the electronics the tank is not empty and the upper float tells the electronics in its down position that the tank needs the aux pump to run. I have studied the wiring diagram and schematic for hours and I was Navy Electrician so I know up to a point how to read the schematics. I get lost in the complexity of the relays interactions, and the fault indicator module, since the fault indication module seems to be involved when the aux pump should run. There are NO warning lamps except when I make the low fuel float at the bottom position, then the fault lamp no fuel comes on. Also the connectors with the screw bottoms in the rear panel, do I screw them out with the twisty idem at the bottom of the plug, or do I simply rotate the twists screw then a quarter or half turn then pull up. I don't want to assume I am disconnecting the jacks right and mess them up. So I don't pull them too hard. I want to see if all that is going on is a loose connection, or high resistance connection, or a bad relay, or module. I need pin out readings on what voltages to read on S1, and the relays to trouble shoot this. I have and have read the manuals, not enough info on this specific problem. Any ideas would be much appreciated !! Thanks, Jeff