For the opening of the line, eight powerful 0-6-4 tank locomotives were obtained from Beyer, Peacock and Company, fitted with condensing apparatus for working in the tunnel. Designated as Class I, a ninth followed within six months.

The 0-6-4Ts were built with steam and vacuum brakes and steam reversing gear and weighed 68 t. As electrification of the Mersey Railway progressed, the old rolling stock was advertised for sale. The first to be sold was No. 5 Cecil Raikes, which was bought by Shipley Collieries for £750. The last four locomotives (Nos. 1, 7, 9 and 4) were sold to J & A Brown for use on the Richmond Vale railway line in New South Wales, Australia. Following storage at Derby Locomotive Works for a number of years, Cecil Raikes was presented to National Museums Liverpool by the British Railways Board in 1965.

Two of the Class I locomotive have been preserved.