1998 escort diesel starting problems?

My escort van won't start. You turn the key and the starter just clicks but only one click. So i changed the starter for a reconditioned one and still the same problem. i have also changed the alternator as this was found to have a crack in it. This all occured after i was caught in a flood and had hoped changing these parts would fix the problem but to no avail. Any suggestions would be greatly appreciated.