In February 1896 R. M. Broadbent accepted the tender from W.G. Bagnall Ltd of Castle Engineering Works, Stafford, for the first locomotive for the new railway. Sea Lion was delivered to Groudle in May of 1896 and entered service immediately.

Sea Lion is a 2-4-0 side tank having outside cylinders and boilers with marine fireboxes. The original livery of Sea Lion was light olive green with black lining, edged in red (outside panels) and yellow (inside). During the 1930's Sea Lion's livery was mid-brunswick green edged in black, with the name in gold letters shaded with blue.

Specification

• Cylinders (bore x stroke) = 4.5 in x 7.5 in
• Driving wheel diameter = 1 ft 2 in
• Leading wheel diameter = 9 in
• Water capacity = 60 gals
• Fuel capacity = 4.75 cu ft
• Heating surface: tubes = 59 sq ft
• Working pressure (original) = 140 psi
• Weight (working order) = 4 t 12cwt
• Tractive effort (at 85% boiler pressure = 1290lb