British Rail Class 23
The power unit used a Napier Deltic T9-29 9 cylinder engine of 1100 hp driving an EE generator, which powered the four traction motors. After acceptance trials at Doncaster, the locos were based at Hornsey. It had been BR's original intention to work the locos across London on the widened lines but they were found to be too heavy. The first of the class was stopped at Vulcan Foundry whilst EE tried to reduce the weight but this could not be completed to a satisfactory standard.
The locomotives were put to work on King's Cross outer suburban duties such as the Cambridge Buffet Express as well as services from Kings Cross to Moorgate. The locomotives were later banned from Moorgate because of excessive exhaust smoke in the tunnels.
It wasn't long before serious problems were being found with the class. Many engines seized because the shaft driving the auxiliaries from the engine snapped and whipped round rupturing coolant hoses. Other lubrication problems caused seized pistons and cracked cylinder liners. By around 1963, all the locomotives had gradually been moved to Stratford Depot as they failed and were added to the line in store, pending a decision on their future. By this time the locos were based at the new diesel maintenance depot at Finsbury Park.
It was decided by BR and EE to carry out a program to refurbish the class and modify the engines with new parts designed by the engine manufacturer. The locos also had modifications to their nose ends, losing the gangway doors and headcode discs in favour of a central roller blind headcode box. The livery also changed to two tone green with grey roof to mimic that of their larger Type 5 sisters so they looked every bit a 'baby deltic'. The locomotives gradually returned to traffic and became very reliable in traffic except for ongoing coolant system problems. They were unable to redeem themselves however as BR had drawn up the National Traction Plan to rationalise the number and types of diesel locomotives in traffic and they were an obvious target being only a ten strong class. The locos were deemed as non standard and withdrawn between 1968 and 1971. The last two locos in traffic on revenue earning service were D5905 and D5909. Several of the class received full yellow ends whilst still in two tone green, a couple even carried the new double arrow BR symbol. D5909 was the only locomotive to receive the full rail blue livery. D5901 was transferred to the departmental fleet of the Railway Technical Centre in 1969. It worked test trains to and from the RTC until 1975 when it was replaced by a Class 24. The loco was cut up in 1977, still carrying two tone green livey with a grey roof and small yellow warning panel.
|British Rail non-steam locomotives|
|Diesel locomotives - Electric locomotives - DMU - DEMU - AC EMU - DC EMU - Departmental units|
|Diesel shunting locomotives|
|Classes:||01 - 01/5 - 02 - 03 - 04 - 05 - 06 - 07 - 08 - 09 - 10 - 11 - 12 - 13 - 14|
|Pre-TOPS type:||D1/1 - D1/2 - D1/3 - D1/4 - D2/1 - D2/2 - D2/3 - D2/4 - D2/5 - D2/6 - D2/7 - D2/8 - D2/9 - |
D2/10 - D2/11 - D2/12 - D3/1 - D3/2 - D3/3 - D3/4 - D3/5 - D3/6 - D3/7 - D3/8 - D3/9 -
D3/10 - D3/11 - D3/12 - D3/13 - D3/14
|Pre-1955 type:||11001 - 11104 - 15107 - 13000|
|Main-line diesel locomotives|
|Classes:||15 - 16 - 17 - 20 - 21 - 21 (Vossloh) - 22 - 23 - 24 - 25 - 26 - 27 - 28 - 29 - 30 - 31 - 33 - 35 - |
37 - 40 - 41 (Warship Class) - 41 (HST) - 42 - 43 (Warship Class) - 43 (HST) - 44 - 45 - 46
47 - 48 - 50 - 52 - 53 - 55 - 56 - 57 - 58 - 59 - 60 - 66 - 67
|Pre-TOPS type:||D8/1 - D8/2 - D10/1 - D10/2 - D10/3 - D11/1 - D11/2 - D11/3 - D11/4 - D11/5 - D12/1 - |
D12/2 - D12/3 - D13/1 - D14/1 - D14/2 - D15/1 - D15/2 - D16/1 - D16/2 - D17/1 - D17/2 -
D20/1 - D20/2 - D22/1 - D22/2 - D23/1 - D25/1 - D27/1 - D33/1 - KA - KB
|Pre-1955 type:||10000-10001 - 10100 - 10201-10203 - 10800|
|Classes:||70 - 71 - 73 - 74 - 76 - 77 - 80 - 81 - 82 - 83 - 84 - 85 - 86 - 87 - 89 - 90 - 91 - 92|
|Pre-TOPS type:||AL1 - AL2 - AL3 - AL4 - AL5 - AL6 - EB1 - EE1 - EM1 - EM2 - ES1 - HA - HB - JA - JB|
|Departmental:||97 - 97/6 - Eastern - Southern - Other Series|
|Other:||98 - 99 - 15097-15099 - 18000 - 18100|
|Demonstrators:||D0226/D0227 - D0260 - D0280 - D9998 - DHP1 - DP1 - DP2 - GT3 - HS4000 - Janus/Taurus|