The 73 class is a diesel-hydraulic locomotive built by

Walkers Limited Walkers Limited was an Australian engineering company, based in Maryborough, Queensland. It built ships and railway locomotives. The Walkers factory still produces railway locomotives and rolling stock as part of Downer Rail. History In ...

, Maryborough for the

New South Wales ) , nickname = , image_map = New South Wales in Australia.svg , map_caption = Location of New South Wales in AustraliaCoordinates: , subdivision_type = Country , subdivision_name = Australia , established_title = Before federation , es ...

Department of Railways between 1970 and 1973.

History

The New South Wales Department of Railways placed an order in October 1969 with

, Maryborough for 20 B-B shunting locomotives. These were the only New South Wales locomotives to be built in

Queensland ) , nickname = Sunshine State , image_map = Queensland in Australia.svg , map_caption = Location of Queensland in Australia , subdivision_type = Country , subdivision_name = Australia , established_title = Before federation , establishe ...

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 and the Sydney Metropolitan area, as well as at

Goulburn Goulburn ( ) is a regional city in the Southern Tablelands of the Australian state of New South Wales, approximately south-west of Sydney, and north-east of Canberra. It was proclaimed as Australia's first inland city through letters pate ...

had been replaced. In July 1971 a further 30 units were ordered. The last of these arrived in March 1973 and this brought to an end all remaining steam shunting operations in New South Wales.

In traffic

The New South Wales Department of 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. Big floods in March 1976 gave 7323 an opportunity to show off its swimming ability when water covered the line near Bourke and this locomotive was used on a couple of freight trains and a ballast train from

Nyngan Nyngan () is a town in the centre of New South Wales, Australia, in the Bogan Shire local government area within the Orana Region of central New South Wales. At the 2016 census, Nyngan had a population of 1,988 people. Nyngan is situated on th ...

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

Menindee Menindee (frequently but erroneously spelled "Menindie" ) 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 and a population of 551. ...

in 1976 and Hexham 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 scrubbers for use on Eastern Suburbs Railway construction in the 1970s.

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:

Withdrawal

With a reduction in locomotive hauled passenger trains and the closure of a number of yards, withdrawals began in February 1987. By October 1991 only three remained in service with

FreightCorp FreightCorp (formally the ''Freight Rail Corporation'') was a railway operator owned by the Government of New South Wales responsible for intrastate and some interstate rail cargo handling from its creation in January 1989 until it was privatis ...

. One was repainted into

CountryLink CountryLink was a passenger rail and road service brand that operated in regional areas New South Wales, Canberra, Brisbane and Melbourne. Originally created as a business unit (or sub-brand) of the State Rail Authority of New South Wales, it l ...

livery for use as a depot shunter at the

XPT Service Centre The XPT Service Centre is a railway depot operated by NSW TrainLink in , Sydney. History The XPT Service Centre was built within the confines of Meeks Road triangle between the Bankstown, Illawarra and Metropolitan lines immediately south of ...

. Disposals commenced in 1990 with three sold to the

Canberra Railway Museum The Canberra Railway Museum is located at Kingston in the Australian Capital Territory (ACT), next to Canberra railway station on the Bombala railway line. Since May 2018, Canberra Railway Museum has been the trading name of a not-for-profit ...

. Four were sold to the

Manildra Group The Manildra Group is an Australian agribusiness based in Sydney. It was formed in 1952 when Jack Honan purchased a flour mill in Manildra. In 1966 a starch and gluten plant was established in Auburn. In the early 1970s, further starch plants op ...

in 1991. Many were sold to Queensland sugar cane companies for conversion to gauge. A number have also been preserved. 7301 & 7344 were placed on

RailCorp Rail Corporation New South Wales (RailCorp) was an agency of the State of New South Wales, Australia established under the ''Transport Administration Act 1988'' in 2004. It was a division under the control of Transport for NSW since the latter' ...

's Heritage & Conservation Register. 7301 was subsequently scrapped in January 2014.

Preserved

The following are held by recognised preservation organisations: *7307 & 7321: Owned by the Oberon Tarana Heritage Railway, both in Patrick Portlink red and yellow livery"Touring the Classics" ''Railway Digest'' June 2010 page 24 *7320 & 7324: Privately owned, currently stored in Canberra *7329 & 7335: Owned by the

Dorrigo Steam Railway & Museum The Dorrigo Steam Railway & Museum in Dorrigo, New South Wales, Australia is a large, privately owned collection of railway vehicles and equipment from the railways of New South Wales, covering both Government and private railways. The collecti ...

*7344: Owned by

Transport Heritage NSW In 2013, Transport Heritage NSW was established by the Government of New South Wales to manage the State’s rail heritage collection and provide support to the broader transport (bus, tram, rail) heritage sector in NSW following an independent ...

, formerly in the custody of

3801 Limited East Coast Heritage Rail is a not for profit company limited by guarantee formed in June 1985 as 3801 Limited to operate steam locomotive 3801 and its associated rolling stock. The company operated heritage train tours from 1986 until 2017, wit ...

(now East Coast Heritage Rail) until 2017 and from December 2018 is in the custody of the Rail Motor Society and is based at its Paterson Depot. The unit has been repainted in the original Indian Red livery. Vigilance control and an ICE train radio have been fitted and it has also been refitted with buffers to facilitate the Society's main line operations. *7350: Owned by

, stored at the

Broadmeadow Locomotive Depot Broadmeadow Locomotive Depot (NSW depot number 2) was a large locomotive depot consisting of two roundhouse buildings and associated facilities constructed by the New South Wales Government Railways adjacent to the marshalling yard on the Main ...

and restored for use as Depot shunter

Sold

The following units were sold for further commercial operation, some being converted to : *7304, 7306, 7308 & 7341: all stored in original condition at the former North Eton Mill shed and owned by the

Mackay Mackay may refer to: *Clan Mackay, the Scottish clan from which the surname "MacKay" derives Mackay may also refer to: Places Australia * Mackay Region, a local government area ** Mackay, Queensland, a city in the above region *** Mackay Airpor ...

Sugar Limited *7305, 7328, 7330 & 7331: all rebuilt and operational at Farleigh Mill *7309, 7336 & 7347: all stored in original condition at Kalamia Mill,

Ayr Ayr (; sco, Ayr; gd, Inbhir Àir, "Mouth of the River Ayr") is a town situated on the southwest coast of Scotland. It is the administrative centre of the South Ayrshire Subdivisions of Scotland, council area and the historic Shires of Scotlan ...

*7310, 7318, 7325, 7346 & 7348: all rebuilt and operational at Invicta Mill *7313: rebuilt and operational at Pleystowe Mill *7314 & 7339: both rebuilt and operational at Proserpine Mill *7315 & 7319: restored and operational at Shoalhaven Starches,

Bomaderry Bomaderry (locally known as "Bommo") is a town in the Shoalhaven council district area of New South Wales, Australia. At the , it had a population of 8,718 people. It is on the north shore of the Shoalhaven River, across the river from Nowra, the ...

, owned by the

both ex

*7317: rebuilt and operational at Plane Creek Mill *7327 & 7332: both stored in derelict condition at Mackay Sugar Co-op *7337 & 7343: both rebuilt and operational at Marian Mill *7340: restored and operational at Narranderra Mill, owned by the Manildra Group *7349: stored in original form at Pioneer Mill,

Brandon Brandon may refer to: Names and people *Brandon (given name), a male given name *Brandon (surname), a surname with several different origins Places Australia *Brandon, a farm and 19th century homestead in Seaham, New South Wales *Brandon, Q ...

*7322 & 7333: both stored and are now owned by the Manildra Group both ex

CRT Group CRT Group is an intermodal transport company in Australia. It was founded in 1954 as Colin Rees Transport, a taxi truck company in Sydney. In 1981 it became known as the CRT Group, and by the time of its acquisition by QR National in June 2005 ...

*7319 & 7322 & 7333: have been purchased by a local company in Goulburn and are currently stored in the Goulburn Locomotive Depot with 7333 being restored to operating condition inside the roundhouse *7334: is for sale in 2018. https://www.machines4u.com.au/search/Railway+Shunt+Tractor/