Like the other Webb compounds, they proved problematic, so in 1904 George Whale began rebuilding these to simple expansion engines. Fifteen were converted to Class C between 1904 and 1906, 62 to Class D between 1906 and 1909, with the remaining 34 rebuilt by Charles Bowen Cooke to Class C1 between 1909 and 1912.
All Class D locomotives were later rebuilt to Class G1. Some of them, rebuilt to Class G2a, were still running in 1962.[2]
Classification
The LNWR letter classification system for 8 coupled engines (A, B, C, etc.) was introduced in 1911.