The Red Devil

SAR Class 26 No 3450 – The Red Devil

Class 26 4-8-4 "The Red Devil" as originally rebuilt in 1982

“The Red Devil” is the iconic nick-name that was given to SAR Class 25NC No 3450 after David Wardale rebuilt it to become the sole member of Class 26 in 1981.  Wanting the locomotive to create an impression with the general public and in strict contravention of SAR policies, Wardale painted his locomotive “buffer beam red”.  The official name given to the locomotive as originally carried on cast nameplates mounted on the locomotive’s smoke deflectors, was “L.D. PORTA”.

204 pages of Wardale’s 520 page book The Red Devil and Other Tales from the Age of Steam describe in great detail the modifications that were made to what had erstwhile been a poorly performing member of SAR’s premier steam locomotives of the German-built Class 25NC.  The purpose of the modifications was to demonstrate to the South African Railway authorities that their then newly established dieselization policy was mistaken and that modernized steam locomotives incorporating technical improvements developed by Argentinean engineer Livio Dante Porta, would offer demonstrable cost savings in a country that was replete with vast coal resources yet 100% dependent on imports for its oil.

On page 146 of his book, Wardale lists the modifications that were made to 3450 together with a shorter list of planned modifications that were not, in the end, incorporated.  The lists are replicated below, with links provided to pages of this website that offer information on the relevant technology:

Modifications that were Proposed and Implemented

  1. Gas Producer Combustion System*
  2. Lempor Exhaust System*
  3. Kordina
  4. Lengthened and internally aerodynamic modified Master Mechanics smokebox*
  5. Surface type feedwater heater
  6. Enlarged superheater
  7. Superheater booster (tube baffle)*
  8. Enlarged main steam pipes
  9. Enlarged steam chests
  10. New pattern saturated steam-cooled valve liners
  11. New pattern piston valves
  12. Altered valve gear to give the correct motion to the new valves
  13. Herdner starting valves
  14. Modified pistons
  15. Reduced cylinder clearance volume
  16. Improved piston rod packings
  17. Improved valve and cylinder lubrication*
  18. Variable stroke mechanical lubricator drive
  19. Improved cylinder insulation
  20. Improved sanding gear*
  21. Rail washer*
  22. Improved smokebox door seal*
  23. Elimination of causes of unreliability (items requiring frequent running repairs)
  24. Enforced use of full throttle
  25. Mid gear drifting and removal of snifting and bypass valves*
  26. Improved boiler feedwater treatment.
  27. Articulated valve spindles
  28. Improved valve spindle packings
  29. Modified cylinder liners and
  30. Improved valve and cylinder liner material
  31. Raised running boards
  32. Altered exhaust deflectors*
  33. Enlarged coal bunker
  34. Equipment for dispensing water treatment chemicals.

Items marked * were applied by Wardale to his first locomotive conversion: SAR 19D No. 2644.

Modifications that were planned but not implemented

  1. Increased boiler pressure
  2. Conversion to 4-8-2 wheel arrangement to increase adhesive weight
  3. Enlarged ashpan
  4. Ashpan grate
  5. Automatic primary air dampers
  6. Surface treatment of cylinder and valve liners to reduce wear
  7. Internal insulation of non-rubbing cylinder surfaces
  8. Cylinder block steam jacket
  9. Piston tail rods
  10. Improved steam reverser.

Performance Improvement

The locomotive’s performance was transformed by the modifications to the extent that its maxumum power output was increased by some 40% compared to the unmodified Class 25NC, while specific fuel and water consumption was dramatically reduced.  Specifically the following improvements were achieved on test:

  • Reduction in specific coal consumption ranging from about 30% at the lowest speed and drawbar pull, to about 60% at higher speeds and pulls, corresponding to increases in drawbar thermal efficiency of 43% and 150% respectively;
  • Reductions in specific water consumption ranging from about 20% at the lower speeds and drawbar pulls, to about 45% at higher speeds and pulls
  • Speed at the maximum drawbar power was increased from 80 km/h for the Class 25NC to 100 km/h for the Class 26.
  • Maximum equivalent drawbar power increased from 1,980kW at 80km/h for the Class 25NC to 2,870kW for the Class 26 at the same speed – a 43% increase.
  • Maximum predicted drawbar power was 3000 kW at 100 km/h.
  • Max speed capability increased by an indetermined amount because of SAR speed restrictions.  However Wardale believed that the Red Devil would have been capable of operating at 160 km/h (100 mph) had the authorities allowed it.

Problems in Service

Whilst the locomotive performance capabilities were remarkable, they could not be delivered with reliable consistency. This was largely due to the nature of the machine, being an experimental prototype intended for further development, and (in terms of its adhesive weight) rather unsuited to using the enormous power that it was capable of developing without slipping.

Specific problems that arose included:

  • Institutional problems associated with:
    • Lack of support from senior railway officials who were (by then) committed to a program of dieselization;
    • Shortage of operating or maintenance staff who were sufficiently interested in learning the skills needed to get the best out of 3450; as a result, the locomotive was unpopular with crews who were unfamiliar with driving on a fully-opened regulator;
  • Gas producer combustion system: Wardale states that GPCS was one of the great strengths of 3450 when it was going well, but it was also a source of operational difficulties.  These were largely associated with:
    • distributing coal evenly with mechanical stoker
    • slow response with newly-made fire
    • sensitivity to type of coal used
    • ash build-up on the grate
    • disturbed firebed from shaking the grate
  • Superheater problems largely associated with:
    • the use of a second-hand header of poor quality
    • steam leakages cause by poor tube manufacture and header fixings
  • Boiler pump problems associated with the use of a second-hand units taken from (converted) condensing Class 25 locomotives.
  • Slippage caused by inadequate adhesion associated with inadequate adhesive weight to handle the increased power that could be developed.
  • Foaming and priming caused by poor quality antifoam in the boiler (forming an essential part of the water treatment system)
  • Starting difficulties associated with the modified valve gear geometry which limited the maximum cut-off to 65%.  Herdner valves that were fitted to help overcome this deficiency did not perform as well as expected.

When Wardale left South Africa in 1984, there was no-one left with the vision or interest to take the project further and 3450 fell out out favour and never again demonstrated the capabilities that it had with Wardale.  Besides that, it had become an embarrassment to SAR’s “modernization” policies which included the fast-track replacement of steam with diesel traction.

The Red Devil was partially converted back to stardard form through the removal of some of Wardale’s modifications. It was saved from the cutters torch in order to operate special trains, and continued to operate hauling charter and tourist trains up until August 2004.  In April 2018 she was rescued from storage and transferred to Worcester loco works where she was put back into working order before being returned to main line operation in July 2018 as reported in the News section of this website.



Further information about the Red Devil can be found on the following pages of this website:

See also

Post Script: In 2013 this website published an article claiming that in the 1990s the Red Devil achieved a speed of 92 mph on the descent into Poupan on the Kimberley De Aar line.  Wardale refuted the claim, estimating that the locomotive could not have achieved more than 82 mph in the circumstances that were described.  His refutation, in the form of 6 pages of calculations, can be downloaded here.

Notwithstanding, if the locomotive did achieve a speed of 82 mph then it could be entitled to claim a world speed record for steam traction on narrow gauge tracks, currently claimed (according to Wikipedia) by a Japanese 4-6-4 that ran at 80 mph [129 km/h] in 1954.  That The Red Devil was capable of doing so is not in doubt.  In his book (page 287), Wardale predicted that The Red Devil would have had a balancing speed on level tangent track of at least 150 km/h (93 mph) with a 500 tonne load.  Wardale also confirmed on the same page that “3450 was timed at 125 km/h (77.5 mph) downhill between Belmont and Witput on the Trans Oranje Express loaded to 21 coaches, 845 tons tare (about 870 tons gross) in 1991, the fastest ever authenticated speed by an SAR steam locomotive in regular service”.