I recently watched a video in which BNSF moved 12 Locomotives around to a different location due to a shortage of power in that area. When they move these locos in a pack like that, are they all fully fueled when they move them and how many are powered?
Fueling probably depends on railroad policy and fuel availability at different locations.
I believe most railroads have limits on how many powered axles a train can have. The dead engines would still have brakes hooked up, but the traction gear would be isolated.
Special Instructions in Penn Central employee timetables from 1969 limited a consist to no more than 24 powered axles. Individual motor circuits were not to be isolated to stay within the limit.