From the Rolls-Royce experimental archive: a quarter of a million communications from Rolls-Royce, 1906 to 1960's. Documents from the Sir Henry Royce Memorial Foundation (SHRMF).
Diagram showing a modified sump plate and oil drain plug for a Bentley & 25HP to increase ground clearance.
| Identifier | ExFiles\Box 132\3\ scan0016 | |
| Date | 20th November 1933 | |
| BENTLEY & 25HP MODIFIED SUMP PLATE AND OIL DRAIN PLUG TO INCREASE GROUND CLEARANCE VELUMOID WASHER PRESENT PLUG INTERNAL HEXAGON IN DRAIN PLUG (SAME SIZE AS PETROL TANK DRAIN PLUG) .175 MAX (BOSSES DELETED) ROYCE, LTD FT ROOM NOV 20 1933 DERBY. | ||