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).
Oiling issues and modifications for the Phantom III DL series rocker gear.
| Identifier | ExFiles\Box 131\3\ scan0120 | |
| Date | 18th August 1939 | |
| 1113. Rm{William Robotham - Chief Engineer}/GWH.{George W. Hancock - Head Chateauroux} (F). c. Rm.{William Robotham - Chief Engineer} Mx{John H Maddocks - Chief Proving Officer}/SB.{Mr Bull/Mr Bannister}6/G.18.8.39. SWD2 Fodes PHANTOM III. ROCKER GEAR. DL. SERIES. With reference to your Rm{William Robotham - Chief Engineer}/GWH.{George W. Hancock - Head Chateauroux}21/N.18.8.39. we explained to Br.{T. E. Bellringer - Repair Manager} in BY/SB.{Mr Bull/Mr Bannister}6/MG.13.3.39. that the modified drilling of the oil holes in the rocker shaft was likely to dry up the oil supply to the push rods as the bushes became bedded to the shaft, and this memo also instructed them to add small flats on the shaft so as to extend the holes back to their original position. Perhaps N. have overlooked this. As we understood from LA.{L. A. Archer} that not many cars had been sent out with the altered drilling, it did not seem worth pursuing the matter further, but as there is apparently still some doubt about it, we will send another note clearing it up. What is still rather puzzling is why it should be necessary to restrict the oil at all even by plugging the rockers with felt, as the valve guide modification on the hydraulic tappet type of head coped adequately with top overoiling when there was far more oil floating about than there is on the non-hydraulic head. We believe the over-oiling complained of on the DL. series was really due to oil getting past the pistons on certain cars used in London under conditions where the rings never got properly bedded in. Now that 'L' Section rings are being fitted on production, this trouble should disappear. Mx{John H Maddocks - Chief Proving Officer}/SB.{Mr Bull/Mr Bannister}21 | ||