My Kia Sportage has blown two motors in six months

There could be something wrong with the vehicle that is causing engines to blow up, and simply fitting a new engine is leaving it open to the same catastrophic problem(s). A fuel supply or cooling system problem would be just a couple of possibilities and fitting a new engine to a vehicle with such a problem could easily lead to successive blow-ups.

There’s also the possibility that you’ve simply been unlucky. Was the second engine a used one from a wrecking yard or a rebuilt unit? If it was the former, you might find that it was just about ready to expire, and the fact that it was fitted to your vehicle was not a factor. This is why it’s always important to have any second-hand engine tested before it gets fitted. Good quality used engines will come with a written report to prove there’s some life left in them.

There’s also the owner’s approach to a new engine. Were you careful to check the oil and coolant of the new engine once it was fitted and running? A second-hand engine might have an oil consumption pattern you’re not familiar with, and ignoring this important check could see it run dry and expire. Not pointing fingers, but even a 'new' second-hand engine requires a close eye kept on it.