Victorian Railways Y class
Y129 in current PTV / V/Line livery at Southern Cross station
Type and origin Power type Diesel-electric Builder Clyde Engineering, Granville Model EMD G6B Build date 1963–1968 Total produced 75
Specifications Configuration: ​  • UIC Bo-Bo Gauge 1,600 mm (5 ft 3 in) Length 13.28 m (43 ft 7 in) Loco weight 65 t Fuel type Diesel Prime mover EMD 6-567C (first 50) EMD 6-645 (last 25) Engine type V6 2-stroke Aspiration Naturally aspirated Generator EMD D25E Traction motors General Electric 237
Performance figures Maximum speed 65 km/h (40 mph); Y175 upgraded to 95 km/h (59 mph) Power output 480 kW (640 hp)
Career Operators Victorian Railways Number in class 75 Numbers Y101–Y175 First run 1963 Current owner Pacific National V/Line Newport Railway Museum Ettamogah Rail Hub Steamrail Victoria 707 Operations Disposition 11 in service, 14 preserved, 6 stored, 44 scrapped

The Y class are a class of diesel locomotives built by Clyde Engineering, Granville for the Victorian Railways between 1963 and 1968.

In 1963, the first of 25 general purpose diesel-electric locomotives was delivered by Clyde Engineering. As a cost saving measure, they were built with bogies and motors retrieved from scrapped Swing Door electric suburban train sets; the re-use of these components reduced the unit cost of the Y class locomotive from around £52,000 ($104,000) to £40,000 ($80,000).^[1] Two further orders saw the class total 75 by 1968.

Although built to dieselise Victoria's shunting operations and replace steam locomotives on branch line services, they were also used on mainline goods and passenger services, including between Spencer Street and Werribee.^[2]

After closure of branch lines across the state and the end of short pick-up goods trains, use of the class dropped.^[3]

In the 1980s, it is thought that four Y Class locomotives were on standard gauge, typically Nos 101–104.

Withdrawals commenced from 1985 and large-scale scrappings commenced during 1991 and 1992.^[3]

After the mass-withdrawals of the Y fleet up to 1992, engines 101, 102, 104, 150 and 151 were on standard gauge, as 103 had been withdrawn in the late 1980s. Y101 followed in the early '90s after suffering a collision, but it was not directly replaced.

From 1995, under the newly formed V/Line Freight division, engines Y115, Y151, Y152 and Y169 were running trains on standard gauge, and locomotives Y124 and Y142 were confined to shunting at South Dynon. Within a few years Y150 had replaced Y115 on standard gauge, with the latter engine shifting to Ballarat as a yard pilot. Around the same time, Y169 replaced Y102, and Y152 replaced Y104. These two engines were stored at Newport workshops, then transferred to South Dynon's "rotten row" where they sat for about a decade.

Only two engines—Y152 and Y165—were repainted into the V/Line Freight scheme, which was essentially the same as previous with a new decal and a lighter grey.

The 1999 sale of V/Line Freight to Freight Victoria included engines 110, 113, 115, 118–119, 121–122, 138, 150–152, 157, 165, 169, 171 and 174.^[4] Some of these were upgraded by 2002 using traction motors and gear sets cascaded from the Freight Australia A and X Class locomotive upgrades, permitting operation at 80 km/h. This required replacing the original plain whitemetal axle boxes; in the short term they were modified but eventually they were all replaced with custom units, obviating the need for fortnightly lubrication of the bearings. Air conditioning was also fitted.^[5]

On the 17/2/2013 a mass move of Y class occurred to Newport to be distributed to various heritage operators, locomotives on the train consisted of Y127/VAN/Y102/Y143/Y104/Y108/Y125

Today, four are in service with V/Line as carriage yard shunters and fitted with low speed controls,^[6] with others owned by freight operator Pacific National.^[7][8][9] Seventeen units are officially preserved, though only a handful of those are operational.

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