The New South Wales 73 class are a diesel-hydraulic locomotive originally purchased and operated by the New South Wales Government Railways

New South Wales Government Railways

The New South Wales Government Railways was the government department that operated the New South Wales Government's railways until the establishment of the Public Transport Commission in 1972. Although later known officially as the Department of Railways, New South Wales, it was still generally...

 (NSWGR) of Australia

Australia

Australia , officially the Commonwealth of Australia, is a country in the Southern Hemisphere comprising the mainland of the Australian continent, the island of Tasmania, and numerous smaller islands in the Indian and Pacific Oceans. It is the world's sixth-largest country by total area...

, and now operated by a variety of private operators. The NSWGR were in the need of powerful diesel shunting locomotives in the 1960s. They had experimented with the 7101

New South Wales 71 class locomotive

The 71 class is a class of diesel locomotive operated by the New South Wales Government Railways in Australia.- History :Having just completed the construction of 25 broad gauge 650 hp diesel-hydraulic shunting locomotives for the Victorian Railways , Tulloch Limited, with a view to receiving...

 and 7201

New South Wales 72 class locomotive

The 72 class is a class of diesel locomotive built and operated by the New South Wales Government Railways in Australia.- Construction :Locomotive 7201 was a diesel-hydraulic locomotive, with B-B wheel arrangement. Built in the N.S.W.G.R. Water Supply Workshops at Chullora, it performed its first...

. Following an order by Queensland Railways for similar units, the NSWGR placed an order with Walkers Limited

Walkers Limited

Walkers Limited is an Australian engineering company, based in Maryborough, Queensland, which built ships and locomotives. It is still in the locomotive-building business as part of Downer Rail.-History:...

 for 20 B-B units fitted with a Caterpillar

Caterpillar Inc.

Caterpillar Inc. , also known as "CAT", designs, manufactures, markets and sells machinery and engines and sells financial products and insurance to customers via a worldwide dealer network. Caterpillar is the world's largest manufacturer of construction and mining equipment, diesel and natural gas...

 485 kW diesel engine. These were the first NSWGR locomotives to be built in Queensland

Queensland

Queensland is a state of Australia, occupying the north-eastern section of the mainland continent. It is bordered by the Northern Territory, South Australia and New South Wales to the west, south-west and south respectively. To the east, Queensland is bordered by the Coral Sea and Pacific Ocean...

.

Delivery

The first unit was delivered in October, 1970. When the whole of the first order had arrived, all steam shunting on the North Coast line

North Coast railway line, New South Wales

The North Coast Line is the primary rail route in the Mid North Coast and Northern Rivers regions of New South Wales, and forms a major part of the Sydney-Brisbane rail corridor....

 and the Sydney

Sydney

Sydney is the most populous city in Australia and the state capital of New South Wales. Sydney is located on Australia's south-east coast of the Tasman Sea. As of June 2010, the greater metropolitan area had an approximate population of 4.6 million people...

 Metropolitan area, as well as at Goulburn

Goulburn, New South Wales

Goulburn is a provincial city in the Southern Tablelands of New South Wales, Australia in Goulburn Mulwaree Council Local Government Area. It is located south-west of Sydney on the Hume Highway and above sea-level. On Census night 2006, Goulburn had a population of 20,127 people...

 had been replaced. Their presence was an immediate success and a further 50 units were ordered. The last of these arrived in March, 1973 and this brought to an end all remaining steam shunting operations throughout the state.

In traffic

The New South Wales Government Railways purchased the class mainly for shunting and their prohibition from mainline use was 'officially' due to the lack of vigilance controls. However, despite its absence, the class was still seen on many suburban trip workings and when mainline operation was a necessity, there seemed to be no hesitation to use them.

One advantage a diesel-hydraulic locomotive has over a diesel-electric variety is its ability to negotiate up to 300mm of water over the tracks. The big floods of 1976 gave 7323 an opportunity to show off its swimming ability. In March that year, water covered the line near Bourke

Bourke, New South Wales

-Transportation:Bourke can be reached by the Mitchell Highway, with additional sealed roads from town to the north , east and south . The town is also served by Bourke Airport and has Countrylink bus service to other regional centres, like Dubbo...

 and this locomotive was used on a couple of freight trains and a ballast train from Nyngan

Nyngan, New South Wales

Nyngan [pr: ning-g'n] is a town in the central west of New South Wales, Australia. It is located in the Bogan Shire Local Government Area. At the 2006 census, Nyngan had a population of 1,975 people. Nyngan is situated on the Bogan River between Narromine and Bourke, on the junction of the...

 to Bourke and return. At least two other occasions when their water resistance was put to use was Menindee

Menindee, New South Wales

Menindee is a small town in the far west of New South Wales, Australia, in Central Darling Shire, on the banks of the Darling River, with a sign-posted population of 980.-History:...

 in 1976 and Hexham

Hexham, New South Wales

Hexham is a suburb of the city of Newcastle, about inland from Newcastle in New South Wales, Australia on the bank of the Hunter River.Settlement occurred at Hexham in the 1820s when the land was granted to Edward Sparke...

 in 1977.

Multiple unit operation was common, although the flood event at Hexham is the only known occurrence of triple-heading. A number of units were fitted with exhaust gas scrubber

Scrubber

Scrubber systems are a diverse group of air pollution control devices that can be used to remove some particulates and/or gases from industrial exhaust streams. Traditionally, the term "scrubber" has referred to pollution control devices that use liquid to wash unwanted pollutants from a gas stream...

s for use on Eastern Suburbs Railway construction.

Depot allocation

As an example of the spread of the members of the class throughout the system, the fleet was allocated as follows as at 30 August 1977:

Depot	Allocation
Eveleigh	7301–7314; 7317; 7321; 7339–7345
Goulburn	7315; 7316
Cootamundra	7319
Junee	7320 (Actually working at Albury)
Lithgow	7326
Orange	7322
Dubbo	7323; 7324
Parkes	7325
Broadmeadow	7327–7338
South Grafton	7318
Werris Creek	7346 (actually working at West Tamworth); 7347
Yeerongpilly (Queensland)	7348–7350

Withdrawal

February 1987, saw the first withdrawal, regardin unit 7330, for the class. Others quickly followed and, today, only one unit, class leader 7301, remains in the hands of Rail Corp

Rail Corporation New South Wales

Rail Corporation New South Wales is a statutory authority of the New South Wales government. RailCorp owns, operates and maintains the Sydney suburban and interurban rail network which is marketed under the CityRail brand; in addition to operating rural passenger services under the CountryLink...

. It was last used as a shunter at the XPT Maintenance Depot at Meeks Road, Sydenham

Sydenham, New South Wales

For other places called Sydenham, see Sydenham .Sydenham is a small suburb in the inner-west of Sydney, in the state of New South Wales, Australia. Sydenham is located 8 kilometres south of Sydney central business district and is part of the local government area of Marrickville Council...

. This unit would also occasionally transfer carriages to the wheel lathes at either Enfield

Enfield, New South Wales

Enfield is a suburb, in the Inner-West of Sydney, in the state of New South Wales, Australia. Enfield is located 13 kilometres south-west of the Sydney central business district in the local government area of Burwood Council.-History:...

 or Flemington

Flemington, New South Wales

Flemington is an inner western suburb of Sydney, in the state of New South Wales, Australia. Flemington is located 16 kilometres west of the Sydney central business district, in the local government area of the Municipality of Strathfield.-Commercial area:...

.

Scrapping

The following units have been scrapped:

7302, 7303, 7311, 7312, 7316, 7323, 7326, 7338, 7342, 7345.

Preserved

The following are held by recognised preservation groups:

• 7307 Oberon Tarana Heritage Railway
• 7320 Privately owned
• 7321 Oberon Tarana Heritage Railway
• 7324 Privately owned
• 7329 Dorrigo Steam Railway and Museum
  Dorrigo Steam Railway and Museum
  The Dorrigo Steam Railway and Museum in Dorrigo, New South Wales, Australia is a large, privately owned collection of preserved railway vehicles and equipment from the railways of New South Wales, covering both Government and private railways...
  
  
• 7335 Dorrigo Steam Railway and Museum
• 7344 3801 Limited
  3801 Limited
  3801 Limited is a not for profit company limited by guarantee. It was incorporated on 5 June 1985; A.C.N. 002 951 671. The registered office of the company is at Australian Technology Park.- Establishment :...
  
   Leased to them by RailCorp
• 7350 Hunter Valley Railway Trust
  Hunter Valley Railway Trust
  The Hunter Valley Railway Trust is a railway museum located in North Rothbury, New South Wales Australia on the site of the Rothbury Riot...
  
  

Sold

The following units were sold for further commercial operation, some being converted to :-

Sold 73 Class Locomotives

Number	Sold to	Current Location
7304	Mackay Sugar Limited - 610mm	-
7305	Farleigh Mill - 610mm	Mackay Sugar Limited - 610mm
7306	Pleystowe Mill - 610mm	Mackay Sugar Limited - 610mm
7307**	Oberon Tarana Heritage Railway Inc	Oberon NSW
7308	Pleystowe Mill - 610mm	Mackay Sugar Limited - 610mm
7309	CSR Plane Creek Mill - 610mm	-
7310	CSR Limited CSR Limited CSR Limited is a major Australian industrial company, producing aluminium and building products. It is publicly traded on the Australian Securities Exchange. In 2009, it has approximately 10,000 employees and during a period of a major cyclical downturn the company made an after-tax profit of...  Invicta Mill - 610mm	-
7313	Pleystowe Mill - 610mm	Mackay Sugar Limited - 610mm
7314	Proserpine Mill - 610mm	-
7317	CSR Plane Creek Mill - 610mm	-
7318	CSR Limited CSR Limited CSR Limited is a major Australian industrial company, producing aluminium and building products. It is publicly traded on the Australian Securities Exchange. In 2009, it has approximately 10,000 employees and during a period of a major cyclical downturn the company made an after-tax profit of...  Invicta Mill - 610mm	-
7321**	Oberon Tarana Heritage Railway Inc	Oberon NSW
7322	Colin Rees Transport	QR National QR National QR National Limited is the largest rail freight company in Australia and was formerly owned by the Queensland Government. It was created as an independent company on 1 July 2010 when transport and logistics company QR Limited was split into two companies...  (stored)
7325	CSR Limited CSR Limited CSR Limited is a major Australian industrial company, producing aluminium and building products. It is publicly traded on the Australian Securities Exchange. In 2009, it has approximately 10,000 employees and during a period of a major cyclical downturn the company made an after-tax profit of...  Invicta Mill - 610mm	-
7327	Mackay Sugar Limited - 610mm	-
7328	Farleigh Mill - 610mm	Mackay Sugar Limited - 610mm
7330	Farleigh Mill - 610mm	Mackay Sugar Limited - 610mm
7331	Farleigh Mill - 610mm	Mackay Sugar Limited - 610mm
7332	Mackay Sugar Limited - 610mm	-
7333	Colin Rees Transport	QR National QR National QR National Limited is the largest rail freight company in Australia and was formerly owned by the Queensland Government. It was created as an independent company on 1 July 2010 when transport and logistics company QR Limited was split into two companies...
7334	Colin Rees Transport	Wimmera Container Line
7336	Sarina Mill - 610mm	-
7337	Marian Mill - 610mm	Mackay Sugar Limited - 610mm
7339	Proserpine Mill - 610mm	-
7340	Manildra	-
7341	Mackay Sugar Limited - 610mm	-
7343	Marian Mill - 610mm	Mackay Sugar Limited - 610mm
7346	CSR Limited CSR Limited CSR Limited is a major Australian industrial company, producing aluminium and building products. It is publicly traded on the Australian Securities Exchange. In 2009, it has approximately 10,000 employees and during a period of a major cyclical downturn the company made an after-tax profit of...  Invicta Mill - 610mm	-
7347	CSR Plane Creek Mill - 610mm	-
7348	CSR Limited CSR Limited CSR Limited is a major Australian industrial company, producing aluminium and building products. It is publicly traded on the Australian Securities Exchange. In 2009, it has approximately 10,000 employees and during a period of a major cyclical downturn the company made an after-tax profit of... Invicta Mill - 610mm	-
7349	CSR Plane Creek Mill - 610mm	-

Sold into preservation in 2010**