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).
Issues and solutions for the Phantom III hydraulic jacking system.
| Identifier | ExFiles\Box 139\1\ scan0125 | |
| Date | 25th April 1936 | |
| X11616 HHS. C. Ex. Bx. EV.{Ivan Evernden - coachwork} Hs{Lord Ernest Hives - Chair}/Gry.{Shadwell Grylls} W/LdC. E.1/HP.25.4.36. Phantom III Hydraulic Jacks. With further reference to the above Hs{Lord Ernest Hives - Chair}/Gry.{Shadwell Grylls}1S/KW. 22.4.36, I note that there was insufficient fluid in the replenishment tank, and this accounted for not being able to complete the jacking of the car. It is rather useful to note that a lot of fluid has to leak before it becomes impossible to jack either the front or the rear end of the car alone, and I take it that the system does not get out of order when the end of the fluid is reached and the pump starts trying to push air in. With regard to the modifications to the front brake linkage failing to prevent the brakes binding on maximum rebound, I think this is a matter that should be attended to as we are bound to have a crop of objections if the wheels cannot be turned for washing. Referring to your third paragraph, concerning the instability of the car, I believe it will be found in practice that only one end will be jacked up at a time. I do not think the proposal to use one jack at a time is practicable with the jacks on the frame at the front end, as it would mean doing nearly the same work raising the front of the car with one jack as we do now with two. These jacks also are not suitable for taking the severe side strain either on the front or the rear, which would arise with one wheel jacking. The Sessions people have had some experience with this problem, and to overcome the difficulty they definitely laid down their scheme to use the two jacks simultaneously, either on the front or rear ends of the chassis. With regard to the amount of work required for jacking up, I personally arranged a grip half way down the handle, so that the rams could be quickly and easily filled to the point where they contacted with the road surface, after which the full length of the handle would be required. For a big car like Phantom III the expenditure of energy required is not really over much. E.{Mr Elliott - Chief Engineer} | ||