Guaqui-La Paz 2-6-0 Locomotives in Bolivia

Class Huayna Potosi (Locobase 21072)

Data from FF CC de Bolivia 1958 Locomotive Diagrams supplied in August 2022 by Allen Stanley from his extensive Rail Data Exchange collection. See also [], accessed 19 August 2007, and Martin Coombs, Bolivian steam locomotive list (October 2020), downloaded from []), p. 11. Works number was 41215 in 1906

Small, slow (45 kph/28 mph), overmatched by any ruling grade over 1%, the 4 nonetheless remained in service for at least 7 decades.

The 4's owner--which connected the capital at La Paz with the lake steamer at Lake Titicaca--originally planned to run on the standard gauge. But its loading gauge would have cost more that could be afforded. In the opposite direction, resorting to a 760 mm gauge wouldn't have cost any less and building the G a La Paz to the metre gauge would have permitted easy link-ups with northern Argentine railways.

Class La Paz (Locobase 21090)

Data from FF CC de Bolivia 1958 Locomotive Diagrams supplied in August 2022 by Allen Stanley from his extensive Rail Data Exchange collection; and DeGolyer, Volume 25, p.8.. See also [], accessed 19 August 2007, and Martin Coombs, Bolivian steam locomotive list (October 2020), downloaded from []), p. 11. Works number was 20642-20643 in July 1902.

Sized to burn Australian coal or equivalent, the firebox presented a sizable heating surface area, but the grate seems too small to support even the modest boiler fitted to this pair. An earlier engine from Baldwin (works number 18727 in March 19010 had a slightly smaller firebox but was otherwise very similar. Originally to be name La Paz, it was renamed General Pando

The later Rogers engine shown in Locobase 21072 offered a grate of somewhat greater area.

NB: FCVA tube heating surface of 54.16 sq m (583 sq ft) seems to have been calculated from the inside (fire side) diameter. But the evaporative heating surface area shown appears to use the external diameter. Locobase uses the external diameter to reconcile the two measurements and bring the superheater ratio down to a still-high, more likely value.