MaK G 1204 BB
Type and origin Power type Diesel-Hydraulic Builder Maschinenbau Kiel (MaK) Build date 1981–1991[1] Total produced 18
Specifications Configuration: ​  • UIC B'B' Gauge 1,435 mm (4 ft 8+1⁄2 in) Wheelbase bogie centre 5.800 m (19 ft 0.3 in)[1] Length 12.500 m (41 ft 0.1 in)[1] Width 3.100 m (10 ft 2.05 in)[1] Height 4.220 m (13 ft 10.14 in)[1] Loco weight 72–88 t (71–87 long tons; 79–97 short tons)[1] Fuel capacity 2,500 L (550 imp gal; 660 US gal)[1] Prime mover MTU 12V 396 TC13[1] Transmission Voith hydraulic L5r4U2[1]
Performance figures Maximum speed 42 km/h (26 mph)-80 km/h (50 mph)[1] Power output 1,120 kW (1,500 hp)[1]

The MaK G 1204 BB is a four axle B'B' diesel-hydraulic locomotive with and off centre cab design built by MaK in Kiel, Germany. Eighteen of these light freight and shunting locomotives were built which were used mostly on German industrial railways, two units have worked for the Swiss Federal Railways and received the class designation Am 842.

History and design

The class are development of the 1978 MaK G 1202 design; both locomotives have the same exterior dimensions but the G 1204 has a 1,120 kW MTU 12V 396 of slightly increased power over the MTU 12V 331 engine used in the G 1202.^[1][2]

Operators

Ruhrkohle AG operated 6 of the class, Wanne-Herner Eisenbahn und Hafen 2, NIAG 2, Osthannoversche Eisenbahnen 2, Westfälische Landes-Eisenbahn 2, and Sersa of Switzerland 3,^[1] with one locomotive operating under a number of different companies.^[3]

Two units originally working for Sersa were transferred to the Swiss Federal Railways in 1993 and operate as SBB Am 842.000 and SBB Am 842.001.^[4][5]