| NZR J class | |
|---|---|
| J 1211 being serviced before departure from Napier. Photo by Joseph Christianson | |
| Power type | Steam |
| Builder | North British Locomotive Works, Glasgow, Scotland |
| Build date | 1939 |
| Configuration | 4-8-2 |
| Gauge | 3 ft 6 in (1,067 mm) Cape gauge |
| Wheel diameter | 54 in (1.4 m2) |
| Wheelbase | 34 ft 10 in (10.6 m) |
| Length | 66 ft 11 in (20.4 m) |
| Weight on drivers | 44.45 long tons (45.16 t) |
| Locomotive weight | 68.55 long tons (69.65 t) |
| Tender weight | 40.35 long tons (41.00 t) |
| Locomotive & tender combined weight |
108.9 long tons (110.6 t) |
| Fuel type | Coal [1] |
| Fuel capacity | 6.0 long tons (6.1 t) |
| Water capacity | 4,000 imp gal (18,000 L) |
| Boiler pressure | 200 psi (1,400 kPa) |
| Feedwater heater | ACFI |
| Firegrate area | 39.0 square feet (3.6 m2) |
| Heating surface: Total |
1,469 square feet (136.5 m2) |
| Superheater area | 283 square feet (26.3 m2) |
| Cylinders | 2 |
| Cylinder size | 18 × 26 in (46 × 66 cm) |
| Valve gear | Baker |
| Tractive effort | 24,960 lbf (111.0 kN) |
| Number in class | 40 |
| Number | 1200 - 1239 |
| Locale | All of New Zealand |
| First run | 1939 - 1940 |
| Last run | 1964 - 1967 |
| Retired | 1964 - 1971 |
| Scrapped | 1969 - 1971 |
| Current owner | Mainline Steam, Steam Incorporated |
| Disposition | Withdrawn; 12 rebuilt as JB, 3 preserved |
The NZR J class steam locomotives were a class of locomotive used in New Zealand. Following the success of the K class on NZR main lines, there was an urgent need for a modern, powerful locomotive capable of running over secondary lines laid with lighter rails. Thus a new "Mountain" 4-8-2 type locomotive was designed and classified by NZGR as the new class J. The 40 locomotives were all built by North British Locomotive Works, Scotland. They should not be confused with the members of 1874's J class, the first tender locomotives to operate in New Zealand.
The class had a notable appearance with the boiler being partly streamlined after the style of the New Haven Railroad's J400 class, and was also similar to the Norfolk and Western Railway class J and the NSWGR 38 class. The J class incorporated all the latest ideas of the KA class but a noteworthy departure was the use of the Baker valve gear. The tender was of the Vanderbilt type.
Twelve J class locomotives were converted to oil burning and reclassified as JB class, and the bullet nose streamlining was gradually removed.