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).
Petrol system tests for the Phantom III, focusing on pump noise issues.
| Identifier | ExFiles\Box 91\2\ scan0281 | |
| Date | 20th August 1937 | |
| CHATEAUROUX. To. Rm.{William Robotham - Chief Engineer} c. Rm{William Robotham - Chief Engineer}/IBD. c. Rm{William Robotham - Chief Engineer}/GWH.{George W. Hancock - Head Chateauroux} 32-EX. PHANTOM III. Petrol System Tests. 1st Test. 300 miles on scheme with pipe through dash and third high pressure pump on bonnet side strip in parallel. The air temperature did not rise above 23°c during the run, and the running U.B.temperature was 55°c. The pumps gave no trouble under these conditions, but as soon as the car slowed down for a village and the U.B.temperature rose to 62°c or over, the third pump under the bonnet became very noisy, and when tested by itself immediately after, it was found to starve the maximum speed down to 80 MPH. Under exactly the same conditions and the frame pumps only working and the third pump switched off, there was no noise in villages, and either half would give maximum speed. We are asking for complaints of noise if we try to run this scheme. 2nd Test. High pressure pump in frame only and direct pipe behind dash. No trouble was experienced up to air temperatures of 23°c reached, and the loud noise complained of with three pump scheme in villages did not occur. The ordinary working noise of the pumps was audible with either scheme being transmitted along the pipes to the dash. This would scarcely be noticed under ordinary running conditions, but was very bad when priming and would no doubt be bad when the pumps work hard at high air temperatures. We attribute this to the pipe being inside the body and rigidly fixed to the dash. A scheme of noise insulation will be required. Rm{William Robotham - Chief Engineer}/IMW.{Ivan M. Waller - Head of Chateauroux} Ivan M.{Mr Moon / Mr Moore} Waller. | ||