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).
Instructions on fitting a Zenith petrol filter to a 20 HP car and resolving air bubble issues.
| Identifier | ExFiles\Box 44\1\ Scan096 | |
| Date | 1st February 1927 | |
| W/N. X3700 Hs{Lord Ernest Hives - Chair}/Rm{William Robotham - Chief Engineer}3/LGL.2.27. ZENITH PETROL FILTER. We send you herewith blueprint indicating how the Zenith petrol filter should be fitted to the 20 HP. car. Some difficulty may be experienced in expelling all the air from the filter when it is first fitted. To accomplish this, the car should be rocked until the air bubbles pass through the air release provided. We have taken the matter up with the Zenith Filter Co. and they are modifying their filter to overcome the difficulty. Hs{Lord Ernest Hives - Chair}/Rm.{William Robotham - Chief Engineer} | ||