In theory the type 2's should have had about 5 mk 1's, six at a push, the couple of type 3's would have been pulling about 8 whilst the type 4's should have got up to about 12 mk 1's. (The odd one out is the class 33 - just a type 3, it really seems as if it should have been a type 2.)
In practice all of the diesels were thrashed well beyond what they were originally designed for !
It was a question of expediency over reliability and longevity. The steam engines seemed to be able to cope with overloading, perhaps because it had gone on for so long or perhaps the workshop routines were better able to repair the worn out parts.
For the diesels, the overloading shortened the life of the engine so that some had a noticably better performance after having a scheduled visit to the shops. My impression (not based on hard evidence) was that the Sulzer engines were not as good at surviving thrashing as their English Electric competitors but latterly, the class 50 seemed to be worn out so who knows ? Perhaps the Sulzers were more highly stressed than the EE engines.
In the early days when the diesels were not as reliable as they later became, it wasn't unusual to see the smalle classes doing the work of the bigger stuff, so you could probably model what length train you fancy.
In practice all of the diesels were thrashed well beyond what they were originally designed for !
It was a question of expediency over reliability and longevity. The steam engines seemed to be able to cope with overloading, perhaps because it had gone on for so long or perhaps the workshop routines were better able to repair the worn out parts.
For the diesels, the overloading shortened the life of the engine so that some had a noticably better performance after having a scheduled visit to the shops. My impression (not based on hard evidence) was that the Sulzer engines were not as good at surviving thrashing as their English Electric competitors but latterly, the class 50 seemed to be worn out so who knows ? Perhaps the Sulzers were more highly stressed than the EE engines.
In the early days when the diesels were not as reliable as they later became, it wasn't unusual to see the smalle classes doing the work of the bigger stuff, so you could probably model what length train you fancy.
