I was hoping that I might be able to ask a few questions about the capabilities of Class 37/4 locomotives to work with Mk2f DBSOs. I am aware that DRS has been operating these on Cumbrian coast services in recent years, but I am wondering when and how these locomotives acquired a push-pull capability?
The main questions that I have are:
1. What push-pull equipment is fitted to the 37/4s (i.e. were these locomotives retrofitted with suitable equipment to ensure compatibility with the DBSOs; did they already have the capability through blue star multiple working equipment; or is there another technical explanation)?
2. If they had to be retrofitted with push-pull equipment, when was this done?
3. If the push-pull capability existed from the outset using multiple working equipment, is anyone aware of any occasions when 37/4s substituted for 47/7s on the ScotRail Express services between Edinburgh, Glasgow and Aberdeen in the 1980s, making use of push-pull working?
4. If they did not have push-pull capability when initially rebuilt as 37/4s, is anyone aware of them working sets of ScotRail Express push-pull rolling stock on a pull-only basis (as occasionally happened with Class 47s in the event of unavailability of a 47/7 or a fault in the push-pull equipment)?
Any information is very much appreciated!