Every so often on here you hear about a certain loco or unit being a good one or a bad one compared to it's classmates
Presumably this is as a result of all the components and adjustments internally lining up at the good or bad end of the ranges of permitted tolerance, although I understand 47501 was known for going like the clappers, but going pop often, presumably as a result of a strong engine overloading other parts?
What I really don't understand is why the bad ones seem to stay like that for an extended period? Surely doing the work to make them at least an average one is worthwhile?
Presumably this is as a result of all the components and adjustments internally lining up at the good or bad end of the ranges of permitted tolerance, although I understand 47501 was known for going like the clappers, but going pop often, presumably as a result of a strong engine overloading other parts?
What I really don't understand is why the bad ones seem to stay like that for an extended period? Surely doing the work to make them at least an average one is worthwhile?