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).
Proposed modifications to the Bentley 111 starter carburetter unit to eliminate air intake whistle and prevent fire risk from petrol spillage.
| Identifier | ExFiles\Box 99\1\ scan0029 | |
| Date | 19th August 1938 | |
| BV/EC c. RM{William Robotham - Chief Engineer}/IMW.{Ivan M. Waller - Head of Chateauroux} 408 DA.{Bernard Day - Chassis Design}1/G.19.8.38. Noted BENTLEY 111 - STARTER CARBURETTER UNIT. Please receive herewith :- E.CD.835 Air Silencer and Petrol Catch Bowl for Starter Carburetter - Bentley 111. In order to eliminate the air intake whistle, we have shown a resonance type of silencer fitted to the starter carburetter, the shape of the silencer is dictated by surrounding conditions, but the proportions and volumes will need confirming by trial. The fitting of the silencer does not call for any alteration to the starter unit other than a re-adjustment of the jet needle locating plug after fitting the silencer base plate. We have shown a free breathing petrol catchbowl on the starter jet air bleed hole, to deal with the squirting of a small quantity of petrol here, when the engine stops whilst the starter unit is in operation, thus creating a risk of fire. The alternative to the bowl, is a large diameter drain pipe carried down through the undersheets which will not restrict the supply of air at atmospheric pressure for the air bleed, and which will, of course, be more costly and more unsightly than the bowl. The air bleed hole in float chamber die casting requires tapping out to suit the bowl connection. Will you please detail and instruct the required parts for this experiment as soon as possible. DA.{Bernard Day - Chassis Design} | ||