Gettin Off..Road

I bought my first XJ last month (second one for my son a couple days later, hope to make it a new bad habit). Its a 93, 4.0 HO, manual transmission. 4WD. After driving it for a day or 2, fuel pump got noisy. Then it stopped working. I won't bother you with the story of how I chased a lack of spark problem for hours, due to pump taking out the ignition 30A fuse. Pump measures a virtual short across the connections. About an ohm. Confirmed 12V to pump connector, only stays for a half second or so. Only thing I know for sure is the pump is bad. Replaced it. Worked perfectly....For about 40 miles. Pump became noisy, then stopped, ignition fuse burnt, pump measures shorted. I looked at the ad from when I bought the great running XJ, and noticed it said the previous owner had just replaced the fuel pump.
I have looked at whatever schematics I can find. I have confirmed wiring is correct. Am familiar with the ballist resistor circuit. My problem...my problem right now....What can cause a fuel pump to short out?? Any help would be appreciated.

Caish

I would clean and check the ground.
It might be trying to pull ground through the fuel.
Much like a tail light will burn dim with 12v with a bad ground.