Western Maryland 2-8-8-2 "Chesapeake" Type Locomotives

Class L1 (Locobase 331)

Data from a table in January 1917 issue of Railway Mechanical Engineer, supplemented by data from WM MISC steam locomotive diagram book supplied in May 2005 by Allen Stanley from his extensive collection.

L-series Mallet compounds came in 3 batches, all of which had the same simple (as listed) and compound TE (105,600 lb).

L1s (900-910, possibly a broken series) put 451,800 lb on the drivers and had a total engine weight of 506,500 lb.

L1-a (911-915) drivers supported 455,600 lb and total weight was 503,100 lb.

The L2 class numbered 916-925 and are shown in Locobase 8888.

Drury's (1993) wry comment on the effect on top speed of 52" drivers and 40" LP cylinders: "...the freight timetables must have listed days instead of hours and minutes."

Class L1/L2 with larger grate (Locobase 8888)

Data from WM - 1 - 1936 steam locomotive diagram book supplied in May 2005 by Allen Stanley from his extensive collection.

Lima's third batch of big Mallets weighed a bit more than the L1s (for which, see Locobase 331), but were otherwise almost identical. Some of the class had Baker valve gear, some were fitted with Walschaert valve gear. At some later date, several of the L1s and L2s had their grates stretched from 120" to 160", which increased the grate area to 100 sq ft and the firebox to 530 sq ft. Locobase suspects this was a result of eliminating a combustion chamber ahead of the firebox.

Specifications
Class	L1	L1/L2 with larger grate
Locobase ID	331	8888
Railroad	Western Maryland (WM)	Western Maryland (WM)
Whyte	2-8-8-2	2-8-8-2
Road Numbers	901-915	916-925
Gauge	Std	Std
Builder	Lima	Lima
Year	1915	1917
Valve Gear	Walschaert	Baker
	Locomotive Length and Weight
Driver Wheelbase	15'	15'
Engine Wheelbase	56.67'	56.67'
Ratio of driving wheelbase to overall engine wheebase	0.26	0.26
Overall Wheelbase (engine & tender)	91.14'	91.14'
Axle Loading (Maximum Weight per Axle)	58700 lbs	60300 lbs
Weight on Drivers	451800 lbs	469900 lbs
Engine Weight	506500 lbs	504900 lbs
Tender Light Weight	209500 lbs	224600 lbs
Total Engine and Tender Weight	716000 lbs	729500 lbs
Tender Water Capacity	10500 gals	12500 gals
Tender Fuel Capacity (oil/coal)	20 tons	20 tons
Minimum weight per yard of rail on which locomotive could run	94.12 lb rail	97.90 lb rail
	Geometry Relating to Tractive Effort
Driver Diameter	52"	52"
Boiler Pressure	210 psi	210 psi
Cylinders (dia x stroke)	26" x 30"	26" x 30"
Low Pressure Cylinders (dia x stroke)	40" x 30"	40" x 30"
Tractive Effort	97877 lbs	97877 lbs
Factor of Adhesion (Weight on Drivers/Tractive Effort)	4.62	4.80
	Heating Ability
Firebox Area	404 sq. ft	530 sq. ft
Grate Area	80 sq. ft	100 sq. ft
Evaporative Heating Surface	5693	5768
Superheating Surface	1264	1380
Combined Heating Surface	6957	7148
Evaporative Heating Surface/Cylinder Volume	308.81	312.88
	Computations Relating to Power Output (More Information)
Robert LeMassena's Power Computation	16800	21000
Same as above plus superheater percentage	19852.35	25054.28
Same as above but substitute firebox area for grate area	100254.37	132787.69
Power L1	7962.28	8691.81
Power MT	310.82	326.23