Jamaican Government 4-8-0 Locomotives in Jamaica

Class 27 (Locobase 20707)

Data from D[ennis] Rock Carling, 4-8-0 Tender Locomotives (New York: Drake Publishers, Inc, 1972), p. 28 and serial 46 on table IV [4], pp.98-99. See also P C Dewhurst, "The Jamaica Government Railway and its Locomotives", Locomotive Magazine, Volume 25 (15 January 1919), pp. 4-7; and ibid

(15 October 1919), pp.169-170. See Dewhurst's report on the JGR's origins, structure, and locomotives beginning with a four-page summary in The Locomotive of 15 January 1919.

These were the first Twelve-wheelers produced for the JGR. Carling comments that they were small for North American practice, but had many of the same attributes. One was driving on the second axle and the leading drivers were flangeless. An experiment with flanging the lead drivers and stripping the flanges off the main drivers failed and the original arrangement was restored.

Beginning in 1914, all three were fitted with a larger boiler; see Locobase 20708.

Class 27 (Locobase 20708)

Data from D[ennis] Rock Carling, 4-8-0 Tender Locomotives (New York: Drake Publishers, Inc, 1972), p. 28 and serial 48 on table IV [4], pp.98-99. See also C Dewhurst, "The Jamaica Government Railway and its Locomotives", Locomotive Magazine, Volume 25 (15 October 1919), pp. 170-171.

Thirteen years after the JGR's first Twelve-wheelers were delivered by Kitson (Locobase 20707), the railway fitted a substantially larger slab-sided Belpaire boiler and firebox. Evaporative heating surface area increased by 50%, because of a 54% increase in direct heating surface area and an increase of 24 in tube count, the new ones have a slightly larger diameter. . As a result, boiler and grate demand fell considerably.

P C Dewhurst reported n 1919 that the locomotives, "especially after rebuilding with the new boilers, are giving excellent service."

Class G (Locobase 12787)

Data from Baldwin Locomotive Works Specification for Engines as digitized by the DeGolyer Library of Southern Methodist University Volume 31, p. 146. See also P C Dewhurst, "The Jamaica Government Railway and its Locomotives", Locomotive Magazine, Volume 25 (15 November 1919), p.195. Works numbers were 32475-32476 in December 1907.

Included in the specs that would determine the size and power of this pair of Twelve-wheelers (and presumably the Mikados described in Locobase 12786) was the requirement that each one pull a trailing load of 200 gross (and long) tons up a 3 1/2% grade that had curves with a 297-ft radius (about 12 degrees) at 15 mph. An extended wagon top boiler was joined to a Belpaire firebox. All drivers were equalized and the leading bogie used swing-links suspended from two points.

A superheated version of this design came on the railway in 1914; see Locobase 12788.

Class L (Locobase 3227)

Data from"Recent Designs of Twelve-Wheel Locomotives," Railway Age, Volume 71, #6 (6 August 1921), pp. 251-252. See also DeGolyer, Volume 63, pp. 343+. Works numbers were 52589-52591 in November 1919, 52916-52917 in January 1920, and 52989 in February.

The RA reported that Baldwin had been supplying Twelve-wheelers to Jamaica since 1907. They operated in both freight and passenger service. According to RA, they were especially designed to work mainline service in the hilly sections "...where heavy and long grades occur, with many curves of long radius."

Such a comment suggests that the designers took pains to provide for lateral movement of some or all of the driving axles. And indeed, the specification requires that "special attention to be paid to locomotive, especially engine trucks, to see that it will readily traverse curves of 24 degrees." The locomotives also had to tackle 3 1/3% uncompensated degrees.

Class L-1 (Locobase 14783)

Data from"Recent Designs of Twelve-Wheel Locomotives," Railway Age, Volume 71, #6 (6 August 1921), pp. 251-252. See also DeGolyer, Volume 63, pp. 343+. Works numbers were 52916-52917 in January 1920, and 52989 in February.

These three Twelve-wheelers were identical to the three that had come from Baldwin in 1919 (Locobase 3227) except for the critical modification to the boiler in the form of a superheater.

Class M (Locobase 970)

Data from Export Locomotives section of 1947 Locomotive Cyclopedia. See also "Heavy 4-8-0 Locomotives, Jamaica Government Railway", The Locomotive, Volume 27 (15 June 1921), pp. 142-143; and "New 4-8-0 Type Locomotives for the Jamaica Government Railways', Railway Engineer, Volume 43, No 3 (March 1922), pp. 118-119. Works numbers were 1623-1629.

Although they had capped stacks, polished cylinder heads, and a clean look to their boilers, these engines' bones were North American. They filled the JGR's "liberal" loading gauge and were bigger than the Baldwin L-1s described in Locobase 14783

Operating a 4-8-0 on the steep grades and tight curves called for "special features" according to LM. (The RE report attributes their inclusioni to Locomotive, Carriage and Wagon Superintendent P C Dewhurst.) Only 1/3 of the adhesion wheel base was rigid, wide tires on flangeless lead drivers, and rear drives with significant lateral play flexing to accommodate. Three-point suspension link bogies resisted lateral movement to steer the engines into curves at 25 mph (40 kph).

At the time of the LM rerport, very little flange wear had shown up 'notwithstanding the abnormal amount of curves they continually encounter in service." Climbing the long gradients at a steady 10 mph (16 kph) with 195-205 ton trainloads showed their generous heating dimensions while their power dimensions meant a 1,740 ton load at 15 mph (24 kph) on the "normal sections." Ten-inch (254 mm) piston valves served the cylinders.