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Ford: F700 30A fuse Keep Blowing, dual fuel tanks, fuel pumps


Question
Have a F700, 429 engine, with dual fuel tanks with electric in tank fuel pumps.  The 30A fuse for the anti-brake and fuel system started to blow fuses, replaced fuse three times within 5 miles, the last time the fuse blew and I installed a new fuse it blew immediately once I turned the switch on.

Answer
check over your fuel system and ABS system for a shorted out wire, a burnt wire or other evidence of such, fuses blow because of an overload, such as a power-to-ground fault. a quick way to tell is to hook a multi-meter to the load side of the circuit (were the fuse was, not the side that is 12 volt hot) and hook the other probe to a good ground, with the meter set to ohm resistance. the lower the ohms the better the contact to ground that's bad in this case