The Y10 (Sentinel D.E.D.G.) "Super Sentinel" Tram Engines

Y10 Sentinel Shunter

During the 1920s, the LNER had much success with steam railcars and shunters built by the Sentinel Company. Hence, in November 1929, the LNER ordered two 200hp double-engine double-geared (D.E.D.G type) Sentinel tram engines for the Wisbech & Upwell Tramway. To comply with regulations for this tramway, they were fitted with cow-catchers and protective side skirts. These were delivered in June 1930, and numbered 8403 & 8404.

These strange engines had a cab at each end. Two standard Sentinel 2-cylinder locomotive engines were at the rear, partly housed in the rear cab. The vertical boiler was located in the front cab, and the water tank was located in the middle. Both cabs had controls, enabling the locomotive to be operated from either end. Unlike the other Sentinel shunters owned by the LNER, coal was fed in near the bottom of the boiler (below the main water space), and not the top.

At the Wisbech & Upwell, it was found that the heavy loads of the fruit season placed a heavy burden on the Y10s. Working flat out, they exhibited excessive coal consumption, and emitted sparks. Hence they were both transferred within a year.

Between December 1930 and February 1931, 8403 ran trials at Ipswich. Three months later (May 1931), both engines were moved to Yarmouth to work the old quayside line. After leaving the Wisbech & Upwell, the cow-catchers were removed from both locomotives.

In February 1934, 9404 was transferred to Kittybrewster (Aberdeen) for more dock work. This was followed by a spell at Leonard's Yard (Edinburgh), before returning to Yarmouth in May 1934.

Due to war-time hazards at East Coast ports, both Y10s were evacuated to Norwich in May 1940. They returned during the following November, and stayed at Yarmouth until withdrawal.

Both Y10s survived into British Railways ownership, although 8187 was withdrawn almost immediately. 8186 was withdrawn in February 1952. 8186 was never officially renumbered to 68186, although a photo exists from 1951 with the BR number chalked on it!

Technical Details

Cylinders (x4): 6.75x9in.
Boiler: Diameter: 4ft 6in
Length: 6ft 5 5/8in
Heating Surface: Total: 199 sq.ft.
Firebox: 51 sq.ft.
Tubes: 108 sq.ft.
Superheater: 40 sq.ft.
Grate Area: 6.5 sq.ft.
Wheels: 3ft 2in
Total Wheelbase: 6ft
Tractive Effort: High gear: 11434 lb
Low gear: 7965 lb
Length: 23ft 2.25in
Weight: (full) 24t
Water Capacity: 600 gallons
Coal Capacity: 12cwt


Neither of the LNER Y10s survived into preservation. I am not aware of any other Sentinel D.E.D.G. types surviving into preservation.


A number of 3d printed kits/scratch aids are available of the Y10. Newman Miniatures produce models for both N and OO.

A narrow gauge variation is also available in 3d printed form for OO9 (9mm gauge 4mm scale). Drawings of a similar narrow gauge Sentinel appeared in the July 1998 issue of Railway Modeller.

Further Information

The LNER Encyclopedia also includes an article devoted to the Wisbech & Upwell Tramway.


Thank you to Peter Hayes (Kamloops, BC) on the LNER listserver who supplied some of the above historical information.