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).
Testing a modified air valve piston for a 20/25 carburettor to fix a sticking issue.
Identifier | ExFiles\Box 102\1\ scan0180 | |
Date | 29th May 1934 guessed | |
20/25 Carburettor Air Valve In order to overcome the complaints of sticking of the air valve we have tried a modified (HS{Lord Ernest Hives - Chair}1224 & HS{Lord Ernest Hives - Chair}13110/1) piston in which a large diameter end is guided by a steel guide at the bottom. We tried this out on 18GW during about 600 miles running & then fitted the valve to a later type carburettor on 20GW c's car with air silencer. We then made up a second similar piston & tried this in 17GW in an old type carburettor. After adoption the 'penny' to suit no difference in the carburetion or acceleration could be found. This modified piston is therefore applicable to all types of 20/25 carburettor, the carburettor itself requiring no modification whatever. | ||