A new lease of life for City of Derby following six-month overhaul

City of Derby, one of our two large passenger diesel locomotives, has undergone a comprehensive mechanical and electrical overhaul, with improvements made to almost every aspect of the locomotive.

The project has been a major undertaking for our workshop team, involving everything from rebuilding the wheelsets and upgrading the braking system to completely rewiring the locomotive and redesigning the driver’s controls.

And, as the finishing touch, City of Derby has been treated to a beautiful new coat of British Railways blue paint, giving her a completely different appearance.

An important member of the Lappa family

City of Derby has been a familiar sight at Lappa Valley since arriving in 2016 and plays a particularly important role in keeping our railway running throughout the year.

During the winter months, she operates many of our Main Railway services, allowing our steam locomotives to enjoy a well-earned rest while essential maintenance takes place.

During the busier summer season, she’s also on hand to haul additional trains, including operating a second passenger service or working in a ‘top-and-tail’ formation, with a locomotive at either end of the carriages.

Having previously undergone a major overhaul during 2020 and 2021, City of Derby has provided many years of dependable service. However, with the locomotive approaching another decade at Lappa Valley, the time was right for some substantial investment in her future.

Six months of engineering improvements

The overhaul has involved an enormous amount of work, much of it taking place behind the scenes in our workshops.

One of the biggest jobs involved removing City of Derby’s wheelsets and sending them to specialists South West Steam Engineering for rebuilding and upgrading.

This work has included wheel reprofiling, new axles, improvements to the chain-tensioning system, uprated chains and servicing of the hydraulic motors.

Meanwhile, back at Lappa Valley, our engineering team has been busy tackling almost every other aspect of the locomotive.

Her 2.8-litre turbocharged Isuzu diesel engine has received a major service, including new oil seals, a timing belt, fresh oil and replacement filters. Improvements have also been made to the cooling system, including fitting a new radiator to help the locomotive cope with the demands of hauling heavier trains.

The hydraulic system has been thoroughly serviced, while one of the most significant projects has been a complete electrical rewire.

City of Derby’s air system has also undergone a substantial upgrade, with a new compressor installed and the braking equipment adapted to work with the standardised fail-safe braking system used across our passenger fleet.

Even the driver’s cab has received attention, with a redesigned dashboard intended to make the locomotive easier and more comfortable for our driving team to operate.

Together, these improvements will help ensure City of Derby remains a reliable and hardworking member of our fleet for many years to come.

A striking new look

While much of the work has been hidden beneath the bodywork, the most immediately noticeable change is City of Derby’s completely new colour scheme.

Previously carrying a different livery, the locomotive has now been repainted in British Railways blue, inspired by the British Rail Class 23 ‘Baby Deltic’ locomotives upon which City of Derby is modelled.

Ben Harding, Operations Director at Lappa Valley, explains:

“Baby Deltic Class 23s, which City of Derby is modelled on, did once wear British Railways blue.

“I think there has to be some creative licence in what we’ve done, because of course you wouldn’t necessarily have seen a Cornish Railways lounging lizard logo on the side of a Baby Deltic!

“But we think she looks absolutely superb.”

The new livery also provides a lovely contrast with City of Truro, our other large diesel locomotive, which carries a green colour scheme.

Ben added: “We chose blue because we felt that City of Truro being green and City of Derby being blue gives a lovely contrast in our diesel fleet.”

The transformation has included plenty of attention to the finishing details, including the restoration of City of Derby’s nameplates.

Ready for many more miles

The six-month project represents a significant commitment to the ongoing care and maintenance of Lappa Valley’s locomotive fleet.

While our steam engines often attract plenty of attention, our diesel locomotives are equally important in ensuring we can operate reliable services throughout the year.

Ben paid tribute to everyone involved in bringing City of Derby back to her best.

“Massive thanks and credit to Jason and the team who have made all of that happen.”

With her extensive overhaul now completed and a new appearance to show off, City of Derby is preparing to re-enter passenger service on our 15-inch gauge Main Railway.

We can’t wait to see her back doing what she does best – carrying families through the beautiful Cornish countryside.

Welcome back, City of Derby. We think you look absolutely wonderful!