New South Wales 79 class locomotive

New South Wales 79 class
7923 at Sydney Central
Type and origin Power type Diesel-electric Builder General Electric Serial number 17938, 17939, 17933, 17934 Model GE 44-ton switcher Build date 1943 Total produced 4 Rebuilder FR Tulk, Perth Rebuild date 1979 Number rebuilt 2
Specifications Configuration: ​  • UIC Bo-Bo Gauge 1,435 mm (4 ft 8+1⁄2 in) Wheel diameter 33 in (838 mm) Length Over headstocks: 29 ft 10 in (9.09 m), Over buffers: 35 ft 2 in (10.72 m) Width 9 ft 6 in (2.90 m) Height 13 ft 2+1⁄8 in (4.02 m) Axle load 9 long tons 16 cwt (22,000 lb or 10 t) Loco weight 39 long tons 0 cwt (87,400 lb or 39.6 t) Fuel type Diesel Fuel capacity 210 imp gal (950 L; 250 US gal) Lubricant cap. 32 imp gal (150 L; 38 US gal) per engine Coolant cap. 40 imp gal (180 L; 48 US gal) per engine Sandbox cap. 8 cu ft (0.23 m3) Prime mover Caterpillar D17000, 2 of RPM range 350-1000 Engine type Four-stroke diesel Aspiration Normally aspirated Generator General Electric GT 555A Traction motors General Electric 733, 4 of Cylinders V8 Cylinder size 5.75 in × 8 in (146 mm × 203 mm)
Performance figures Power output Gross: 190 hp (142 kW) per engine For traction: 175 hp (130 kW) per engine Tractive effort Continuous: 13,000 lbf (57.83 kN) at 7.5 mph (12.1 km/h)
Career Number in class 4 Numbers 7920-7923 Delivered 1943 Preserved 7921, 7922 Disposition 2 preserved, 2 unknown

Importation

In 1943, during World War II, four diesel-electric industrial shunting type locomotives were imported from the General Electric Company, Erie, United States of America by the Department of Supply under Lend-Lease conditions for use at the Dunheved munitions factory in Sydney. It seems that only one unit was used at this facility. Being of the hood type, with a central cab, they could work in either direction without turning.

Operations

7920 in Sydney Yard in September 1969

DE91 (ex 7922) at the National Railway Museum, Port Adelaide in October 2010

In 1945, the BHP became interested in the possible dieselisation at its Australian Iron & Steel works in Port Kembla and one unit was loaned to the company in April. Whilst it proved too light for the tasks of hauling ingots and ladles, it did lead to the commencement of dieselisation five years later.

At the end of that war, they were put into use by the New South Wales Government Railways as shunters at Sydney Central station and Eveleigh Carriage Workshops. They were numbered 7920 to 7923, these being the numbers allocated by US authorities. In April 1948, the Commonwealth Government took 7921 and 7922 for use at Woomera Rocket Range and 7920 and 7923 were purchased by the NSWGR in September that year.

In 1950, the two owned by the Commonwealth Government were transferred to Commonwealth Railways as the DE Class and used as shunters at Port Augusta and Port Pirie. In July 1975 both were included in the transfer of the Commonwealth Railways to Australian National.

Disposal & preservation

In October 1974 the two NSWGR units were sold to the British Phosphate Commission for use on Christmas Island. In 1979 both were rebuilt by FR Tulk, Perth with Caterpillar D3306 engines and lower profile noses. This railway closed in 1987.

Following their retirement in the early 1980s, 7921 returned to New South Wales and is preserved at the New South Wales Rail Transport Museum, Thirlmere, while 7922 is with the National Railway Museum at Port Adelaide.

Further reading

• New South Wales Rail System Locomotives. Sydney: Archives Section, State Rail Authority of New South Wales. 1984.