An economic slump across the country inevitably effected the railway, and less visitors were recorded year-on-year, the peak for revenue having been 1927.  To boost traffic it was mooted to run workmans trains between Douglas and Pulrose where a new large housing estate was being established.

Beyer, Peacock & Co., were contracted to provide a new boiler for No.11 Maitland with this series of locomotives now providing the mainstay of the operational fleet together with No.16 Mannin which was generally used only on the heavy south line boat trains since its arrival.