Electro-Diesels for the 21st Century

Electro-Diesels For The 21st Century

73967 at Crianlarich - Photo by Simon Bendall
Far from its traditional home turf, 73967 leads the 5Y11 10.30 Oban-Polmadie empty stock move into Crianlarich on 27th February 2016 with 73968 bringing up the rear, these being the former 73006 and 73117 respectively. The re-engineering of the Class 73/9s has created a far more capable version of the electro-diesels, even if it did take a while to iron out the initial problems.

It was early in 2013 when news first publicly emerged that GB Railfreight was to undertake a major re-engineering of some of its Class 73 fleet. Despite the electro-diesels being a versatile part of the company’s roster, a number of examples were becoming due for major overhauls while sourcing parts for the near 50 year old locomotives was increasingly problematic. Then there was the type’s perennial Achilles’ heel, the under-powered and overheating-prone 600hp English Electric 4SRKT engine.

This project therefore sought to retain the type’s go anywhere ability but with updated internals to make them fit for the 21st century. The decision to make the substantial investment was initially based on a new contract with Network Rail to carry out specific duties, such as infrastructure monitoring test trains, which should see the rebuilt locos operate into the late 2030s at least. The subsequent award of the 15-year Caledonian Sleeper contract to Serco in May 2014 was a further boost to the project as, with GBRf already lined-up as traction supplier, more Class 73s would be needed to work the Scottish sleeper portions.

Partnering with Wabtec-owned Brush Traction, the cornerstone of the re-engineering was to fit a 1600hp MTU R43 4000 V8 diesel engine and associated Lechmotoren alternator, the Loughborough-based firm already having considerable experience of MTU engines thanks to the earlier HST power car re-engining. The result would be a largely new Type 3 diesel locomotive packed into a Class 73 body but also still retaining the ability to run on third rail electric power. The new engine also offered fuel economy alongside the reliability benefits.

In addition to the new power unit, the suite of modifications included the fitting of pre-heating equipment as a MTU engine ideally needs to be at a minimum of 25°C before it will start and will not be at full capability until above 60°C. Accompanying this was the fitting of a new cooler group, including a larger radiator fan, along with new bodyside and cantrail grilles to provide the increased ventilation required.

The English Electric traction motors were retained but with a new chopper control system for improved performance while the electric train supply (ETS) was altered to be available in both diesel and electric modes. Other modifications included a new silencer recessed into the roof, updated electrical and braking systems, rebuilt cab desks, fitting of AAR multiple working equipment as used by Class 66s, and modernised cab fronts.

73963 + 73964 at Brush Traction - Photo by Craig Adamson
As part of the conversion project, each Class 73 was stripped back to a bare bodyshell and rebuilt from there. Seen inside Brush’s Loughborough workshops on 3rd August 2014, 73963 is in the process of fitting out with its body in undercoat while 73964 behind is still undergoing the structural modifications. It would be the spring of 2015 before they were completed. In the far distance, Freightliner’s 70011 is receiving its cooling system modifications.

Phase 1 Conversions

The first Class 73 to arrive at Brush Traction was 73209 on 1st September 2012, some months before the project was unveiled. This loco had endured a difficult three years after suffering an electrical flashover and subsequent fire damage in August 2009. Duly stored, it was eventually battered back into some sort of life to take up shunting duties at Cardiff Tidal between January and August 2011 but was in poor condition, making it an ideal initial donor.

Two more ‘EDs’ arrived for rebuilding during 2013, 73204 coming in by road during March and 73206 in November, while InterCity Executive-liveried 73205 followed in March 2014 and BR blue 73208 three months later.

73962 at Brush Traction - Photo by Craig Adamson
An employee and families open day was held at Brush Traction on 3rd August 2014, the event including the naming of 73962 after Dick Mabbutt, a then recently deceased Brush engineer. The plain blue livery was seemingly intended as a new variation of the GBRf scheme but when the loco was released in January 2015, the familiar orange around the cabs had been added.

It was September 2014 before a fully completed 73961 emerged from Loughborough for the first time, it moving by road to the Great Central Railway for over a month of testing on the preserved line, this including working its first passenger train, with 45041, on 18th October. A main line debut came on 3rd December with a run to Leicester and back but issues prevented a release to traffic.

The initial weeks of 2015 found 73961 undertaking more test runs from Loughborough to Leicester and Derby before being joined by 73962 late in January for multiple working trials to Hotchley Hill and Leicester. This duo finally departed for Tonbridge West Yard on 11th February to begin training of GBRf staff, this including powering several de-icing trains around Kent during the month and then undertaking circular handling runs with a set of MRA ballast wagons in March.

73961 at Tonbridge West Yard - Photo by Simon Bendall
A shiny 73961 Alison stands in Tonbridge West Yard undergoing static tests on 12th February 2015, less than a day after it and 73962 Dick Mabbutt had arrived from Brush Traction. The well-known footbridge over the yard provides a good view of the extensive roof alterations, especially the repositioned and considerably enlarged radiator fan along with the new exhaust silencer.

March also saw 73963 perform its initial test runs from Loughborough before quickly heading to Tonbridge to join its sisters on training duties, while 73964 did likewise in April. The last of the initial batch of conversions, 73965 was let out on test during June before heading for Tonbridge a month later.

Throughout the summer of 2015, the five Class 73/9s remained on test, seeing occasional use on trains, including visits to Derby, Warrington Bank Quay and Peterborough, amongst the light engine runs in Kent. However, full squadron service eluded them as various ongoing faults brought return visits to Loughborough for attention.

GB Railfreight Phase One Class 73/9s

Phase 2 Conversions

The first step towards creating the Caledonian Sleeper pool of Class 73/9s came in May 2014 with GB Railfreight acquiring the vintage ‘JA’ duo of 73005 and 73006 from preservation. Both had been available for sale for some time with 73005 having languished at Eastleigh Works for four years awaiting repairs that never occurred while 73006 was operational and most recently employed at the Crewe Heritage Centre. The latter ‘ED’ was initially transferred to Eastleigh that month before both moved on to Loughborough in September.

Three more donor locos were acquired in August 2014, GBRf purchasing 73103, 73105 and 73117 from Nemesis Rail at Burton-upon-Trent. Withdrawn by EWS in 1999 and 2000, only 73117 had seen any use in the intervening period, most notably at the Dartmoor Railway where it was repainted in BR blue in 2007. The other two were still as withdrawn and in poor condition after years of storage.

December saw 73105 and 73117 moved by road to Loughborough with 73103 following in January 2015. The last donor loco to arrive for the re-engineering project was 73207 in the same month, this coming north from St Leonards by road after first surrendering parts to enable sister locos to be repaired.

It was late September 2015 when 73966 first emerged from Brush Traction resplendent in Caledonian Sleeper teal, the loco making test runs to first Hotchley Hill and then Leicester before heading for Edinburgh Craigentinny on 6th October. Main line testing commenced a month later, 73966 heading an assortment of sleeper empty stock workings throughout November, where it was joined by 73967 later in the month with both being in action during December.

73967 at Golf Street - Photo by Jim Ramsay
The Class 73/9s reached Aberdeen for the first time on 14th December 2015 when 73966 and 73967 arrived with a rake of Mk. 1 coaches belonging to the Scottish Railway Preservation Society. These were then worked back and forth to Dundee for over a week for training purposes. On the first day of the workings, the 15th, 73967 brings up the rear of the 5Z73 11.09 Dundee West-Aberdeen Clayhills at Golf Street station. The initial plated look for the former headcode display can be seen, this soon seeing alteration to a window.

The Scottish ‘EDs’ displayed a number of upgrades to the original conversions, such as increased fuel capacity along with more powerful electric train supply and revised connections to suit the new Mk. 5 coaches. Additional work included fitting one-piece snowploughs, a RETB aerial on the cab roofs and ETS on/off repeater lights on the side of the light clusters.

When first released, 73966, 73967 and 73968 had their former headcode displays plated up in the same manner as their Southern sisters. However, on all three locos, this was duly altered at each end to become a third window complete with additional windscreen wiper. In the case of 73966 and 73967, they were modified upon returning to Brush in early 2016 while 73968 was done before final release late in 2015. The other three locos had the window from the start.

GB Railfreight Phase Two Class 73/9s

Sleeper Debut

The long-awaited appearance of the rebuilt Class 73/9s atop a Caledonian Sleeper service finally took place on 13th February 2016 thanks to engineering work on the West Highland Line. With the sleeper portion unable to reach Fort William, plans had long been in place for the train to be diverted to Oban. However, the low route availability of the line precluded the use of the normal Class 67 with various traction options considered at one point or another, including using ‘Deltic’ No. 55022 Royal Scots Grey or a hired-in Class 37.

In the end though, the ‘EDs’ were deemed sufficiently well tested to enable their use, all the trains operating in ‘top and tail’ form for both insurance and to save running round at Oban. Thus, 73967 hauled the 1Y11 04.50 Edinburgh-Oban away from the Scottish capital on the 13th with 73968 bringing up the rear, the latter having reached Scotland in the first week of 2016.

With little in the way of servicing facilities for the coaches available at Oban, the decision was made to return the empty stock to Glasgow as the 5Y11 10.30 Oban-Polmadie. The next day saw the train retrace its steps as the 5B01 13.02 Polmadie-Oban in readiness to form the 1B01 19.35 departure to Edinburgh. This method of operation was repeated again on 20th/21st and 27th/28th February with 73967 and 73968 officiating on all the trains.

73967 at Oban - Photo by Simon Bendall
Looking like the sort of formation only found on a model railway, 73967 was on the back of the recently arrived 1Y11 04.50 Edinburgh-Oban diverted Caledonian Sleeper service at its destination on 27th February 2016. Standing in the shadow of McCaig’s Tower and with 73968 at the other end, the formation included Virgin-liveried Mk. 2f RFB 1212 and InterCity BSO 9526, both on hire from Riviera Trains, along with Mk. 3 sleepers 10529 and 10543 still in First Group colours.

On 15th February, 73967 became the first of the class to reach Inverness, topping 67007 on the 1S25 Edinburgh-Inverness and 1M16 return, a pairing that was repeated for more than a week. A month later, 73967 and 73968 reached Aberdeen atop a sleeper for the first time while 73969 arrived at Craigentinny after testing at the same time with 73970 following in June. However, the 1st April 2016 target of squadron service for the Class 73/9s on the sleepers was not achieved with hired-in Class 67s continuing in use.

Reliability Modifications

Throughout 2015 and the first half of 2016, the reliability of both batches of Brush conversions had been less than stellar with several examples requiring repeat visits to Loughborough for attention. While teething troubles with such a project were not unexpected, a serious issue with vibrations affecting the new Lechmotoren alternators was eventually discovered; this being identified as the primary cause of the type’s reliability woes.

Such was the situation in Scotland that from late June 2016 for the rest of the year and into 2017, Class 66s were drafted in to assist on the sleeper services with an example typically heading both the Aberdeen and Inverness portions with a ‘ED’ coupled behind to supply power to the train. Meanwhile, the Fort William portion initially employed double-headed Class 73/9s to provide some measure of insurance against failure before switching to a 66+73 combination in September.

66705 + 73967 at Arbroath - Photo by Jim Ramsay
The second half of 2016 effectively saw the Class 73/9s relegated to the role of a mobile train supply with a Class 66 providing the traction due to the type’s reliability issues. On 22nd July that year, the ex Class 25 ETHELs of the early-mid 1980s are recalled as 66705 Golden Jubilee leads 73967 on the 1A25 04.43 Edinburgh-Aberdeen at the site of the former Elliot Junction, near Arbroath.

To allow investigation work, 73971 was retained by Brush throughout the summer and autumn of 2016, it not being released to Craigentinny until November. An alternator modification programme was soon put in place with all 11 locos heading back to Loughborough in turn for attention, this taking until March 2017 to complete and allowing the use of Class 66 assistance on the sleepers to cease.

The availability of the Scottish examples was not helped by a runaway incident at Craigentinny in December 2016 that left 73969 with a deformed lower cab front after it hit a Mk. 3 coach up on jacks. Such was the difficult nature of the repair and insurance wrangle that it was not released from repair until January 2018.

Dellner Couplings

No sooner had one set of modifications been completed, the Caledonian Sleeper ‘EDs’ began to cycle through Brush once more from April 2017 to receive Dellner couplings. Required to work with the new CAF-built Mk. 5 stock, the installation of the drop-head couplings also required modifications to the snowploughs to give clearance. This programme took until May 2018 to complete, 73970 being the last to be done.

73971 at Kilmarnock - Photo by Ross McKinna
In addition to their regular Caledonian Sleeper workings between Edinburgh Waverley and Fort William/Aberdeen, with occasional runs to Inverness and Carstairs, the Scottish Class 73/9s also see use on empty stock moves. On 3rd July 2018, 73971 leads the 5D74 Kilmarnock Bonnyton Depot to Polmadie through Kilmarnock station with some of the new CAF-built Mk. 5 coaches in tow, these having been for modifications and internal work ahead of entering service in the spring of 2019. The new Dellner coupling can be seen in the raised position due to a run-round being required.

With their reliability issues pretty much cured, the GBRf Class 73/9s settled down on their intended duties both in the north and south of the UK during 2017. That autumn gave some drama on the West Highland Line as a single loco struggled for adhesion, leading to a spate of wheelflats, with the result that this sleeper portion was usually double-headed in the autumn of 2018.

Other notable occurrences, both in May 2018, saw 73967 and 73968 make a class debut at Mallaig atop the Royal Scotsman luxury train along with another visit to Oban, while 73961 and 73965 were a long way from home in the same month with the type’s first visit to Hull, atop a Network Rail test train.

73963 + 73965 at Radwell - Photo by Nigel Gibbs
As part of GB Railfreight’s contract with Network Rail, two of the phase one Class 73/9s must be available at all times for use on infrastructure monitoring test trains. While much of this work is still centred around the erstwhile Southern Region, the locos do work further afield as needed with regular visits to Merseyside and the surrounding area in particular. The ‘EDs’ are thus a regular site on the Midland Main Line transferring to and from Derby. On 27th May 2017, 73963 Janice and 73965 ‘top and tail’ a 3Z27 14.35 Derby RTC-Cricklewood combined plain line pattern recognition and ultrasonic test train at Radwell, north of Bedford.

Dapol OO Class 73

Although the above upgraded Class 73/9s are not currently available in model form, we do currently have in stock a range of the popular Dapol OO model of the class with 73/0, 73/1 and 73/2 variants all available. Seven models are currently part of our Sale of the Century, discounted heavily from their original RRP, with prices starting from just £84! 

Also available on pre-order are some new variants of the model in BR green, NSE, South West Trains, Southern, EWS, Network Rail and Fragonset liveries.

Explore all Class 73s, HERE.

Back