The Sir Nigel Gresley Society has given a further update on the overhaul of the oldest surviving locomotive designed by Sir Nigel Gresley, after it passed its steam test at the workshops of the North Norfolk Railway (NNR) at Weybourne.

The loco – Gresley class N2 GNR No.1744 – moved to the NNR at the end of last year for the final stages of overhaul, which began in 2018.

During the overhaul, it became evident that more extensive work was required than originally thought, which has also meant that the cost is much higher than anticipated.

The need to carry out a large amount of mechanical and boiler work has pushed the cost of the overhaul to around £650,000.

The overhaul was disrupted by the Covid-19 lockdown, and Russia’s invasion of Ukraine added to both costs and timescales.

Work completed this year has included non-destructive testing and examination of the two carbon steel steam pipes that serve from the superheater header to the steam chests.

This involved magnetic particle inspection (MPI) of all historic welds, ultrasonic measuring of the thickness of the pipe, and clamping the two pipes together to form a single unit.

This allowed a hydraulic pressure test to be carried out, which tested the boiler to be tested at pressures up to 255psi, which is 50% higher than its safe working pressure.

The next steps in the overhaul are to fit the no. 17 washout plugs, to finish reassembling the engine, and to carry out a final hydraulic pressure test of the boiler. The superheater header will undergo hydraulic testing to 255psi.

The NNR agreed to initially fund the work to complete the overhaul, on the basis that it will use the loco for a period without charge to recoup the expenditure through revenue.

However, the Gresley Society still needs to raise a further £100,000, so is promoting its N2 Overhaul Completion Club.

It is looking for 100 people who are each willing to donate £1,000 in up to eight instalments, in return for benefits including a signed certificate, the chance to visit the loco under overhaul, and a reserved seat on one of the loco’s first trains after it returns to service next year.

“The Gresley Society was created to preserve a working Gresley locomotive, and we owe it to our founders, and for the benefit and education of today’s generation, to maintain that vision. The progress on No. 1744’s overhaul at the North Norfolk Railway is one more step towards the return of Sir Nigel Gresley’s oldest surviving locomotive to traffic in spring 2026 resplendent in its distinctive Great Northern Railway livery.

“However, The Gresley Society is not yet out of the woods financially and launched a major £100,000 financial appeal with The N2 Overhaul Completion Club to fund No. 1744’s return to traffic which has already raised over £35,000. I’d encourage all LNER lovers who want to see the class N2 paired once again with the Midland & Great Northern Society’s unique set of Quad-Art carriages on the North Norfolk Railway to get on board with our appeal!”

Philip Benham MBE, Chairman of The Gresley Society