I note that at the Centurion Aircraft Engine website they advertise that their certified 2.0s Diesel Aircraft Engine will go 1,200 hours "Time Before Replacement." Is that their way of saying that their engines cannot be overhauled? Buying a new engine every 1,200 will get to be expensive sooner or later. If their engines cannot be overhauled, then WHY? THANKS IN ADVANCE FOR YOUR REPLIES!