Great Northern 4-8-4 "Northern" Locomotives in the USA

Class S-1 (Locobase 261)

Data from 1930 Locomotive Cyclopedia; see also DeGolyer, Volume 81 pp. 503+ . See also Charles R Wood, Lines West (Superior Publishing, 1984), p. 95. (Thanks to Chris Hohl for his 24 November 2023 email reporting the original tender capacities and weight, engine and tender wheelbases, supplying the original axle loading, and the original weight on the drivers.) Works numbers were 60781-60782 in April 1929, 60807-60810 in May.

Heavy dual-service oil-burning engines. GN's signature improved Belpaire firebox was joined to a combustion chamber that contributed 108 sq ft (10.03 sq m) to the firebox heating surface. Charles Wood described the S-1's face as "pump-heavy" with a low-mounted headlight.

Chris Hohl noted that the original Vanderbilt tender weighed 286,900 lb (130,136 kg) when loaded with 15,000 US gallons of water and 5,000 gallons of fuel oil. Original adhesion weight was 270,600 lb (122,743 kg). With that tender, engine and tender wheelbase measured 93 ft 4 1/2" (28.46 m).

It's not clear if these are the tenders described in Baldwin specification's supplemental note paragraph 44 on page 506. In that note, the builder records that "tenders being built on this order will not be used with [the S-1s], they will be applied to locos. operating in freight service." It further advises that they would "not to be equipped with steam heat line nor air signal equipment." In addition, paragraph 381, p 518 added that "Engines only equipped with train signal and steam heat." [Locobase supposes the sentence means "only the engines, not the engines and tenders."]

When the shops fitted 2552 with an all-weather cab, engine and tender wheelbase increased to 96 ft 4 3/8" (29.37 m).

Unlike many other large superpower engines of the time, this design had no arch tubes or syphons. And the Elesco exhaust steam injector was less common than feed water heaters. It was rated at 10,000 US gallon (37,850 litre) capacity. Steam admission through a Superheater Company multilple throttle feeding 14" (356 mm) piston valves. Possibly reflecting the frequently bitter-cold operating conditions, a "Hereafter" note (paragraph 149) requested "Exhaust pipe from cylinder to exhaust injector to be located under boiler between the driving wheels."

Another tweak (paragraph 306, p 516) concerned the report from the railway that "equalizers in the engine's front truck broke", so "Depth of ends of engine front truck equaliers to be increased from 4" to 6".

Only six built before design changed to lighter engines with high drivers (S-2, see Locobase 262). A "Hereafter" note in Baldwin's specification pages (supplement paragraph 275 on page 515 advises: "Valve motion to be of lighter design, similar to PRR locomotives."

They were nonetheless highly serviceable locomotives. Charles Wood wrote that after they were replaced in express service, "in the late thirties and early forties expedited fast freights such aa the fruit specials. Wood explained "The weight coupled with the lower drivers and slightly larger cylinders gave them considerably more 'dig' than the S-2s.

A later refit replaced the friction bearings with roller bearings (one of "relatively few classes on the GN" so equipped.) They endured, claimed Wood, "because of their ability to roll heavy freight at sustained speed ....in the opinion of many enginemen", the S-1s were "about the best dual-service locomotives on the GN."

They remained in service until 1956 (2553), 1957, and 1958.

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Class S-2 (Locobase 262)

Data taken from DeGolyer, Vol 82, pp. 283+ and Great Northern locomotive diagram reproduced on Ben Ringnalda's [] website, last accessed 16 February 2007. See also Charles R Wood, Lines West (New York: Bonanza Books, 1967), pp. 88 inter alia; and The Great Northern Empire Then and Now website at [], last accessed 3 July 2015.(Thanks to Chris Hohl for his 24 April 2015 email noting the use of coal in some GN S-2s and for callling attention to the high weights shown in the specs.) Data differs slightly from the 1930 Locomotive Cyclopedia specs. Works numbers were 61211-61216, 61224-61225, 61237-61242 in February and March 1930.

The S-2 had high drivers and smaller boilers than the earlier S-1 (Locobase 261) and was more completely dedicated to express passenger service. In fact, Charles Wood noted, these were the first 4-8-4s to have 80" drivers and would be the only such engines until 1937. Turning on friction bearings when delivered, the S-2s would get Timken roller bearings in 1945.

Another change was the squaring of the cylinder dimensions so that diameter equalled stroke. This resulted in slightly more cylinder volume. The boiler was fitted with a Sellers exhaust steam injector that could process 4,500 to 7,350 US gallons (17,033 to 27,820 litres) per hour. Even in mid 1940s, the S-2's adhesion and engine weights were only slightly higher than the specified weight limits in the original order.

To save weight, the GN eschewed their by-then standard Belpaire firebox in favor of a radial-stayed firebox. This large cavity had a combustion chamber (111 sq ft/10.3 sq m) as delivered; 22 sq ft (2.05 sq m) of arch tubes were installed later.

Like their predecessors, the S-2s were oil-fired, but the specs required that the frames were "to be arranged on frame with flat surface for future application of stokers." The class burned oil for most of their 25+-year careers and had the only all-welded tenders on the GN. Some S-2s were converted temporarily in the late 1930s to burn coal and trailed tenders carrying 17,000 US gallons of water and 24 tons of coal.

Wood's assessment of the class was mostly laudatory: "Long winded engines, fast and durable, their only fault was a tendency to be very slippery when starting a heavy train." (p. 96). Engineers developed a starting technique when the S-2 was hitched to a freight train that Wood said "[M]uch to the consternation of the Master mechanic" would set the engine's air, pull the engine's throttle, and release the air. "Th added kick would urge tonnage into motion without wild slipping." There was a big risk, however, in the engine "slipping a driver tire and taking the locomotive out of service." (p. 99).

By 1949 the S-2s had been supplanted in Empire Builder service and relegated to secondary duties.