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).
Bentley car's oil pressure issue after braking and advice on driving conditions.
| Identifier | ExFiles\Box 131\4\ scan0047 | |
| Date | 10th February 1937 | |
| To Rm{William Robotham - Chief Engineer}/GWH.{George W. Hancock - Head Chateauroux} from Rm.{William Robotham - Chief Engineer} Rm.{William Robotham - Chief Engineer}7/AP.10.2.37. Thanks for your memos. There is no reason why you should not run the Bentley car until the new connecting rods we have despatched get to Paris, but I think it would be better if you avoided sustained high speeds. With a view to avoiding accidents, I would suggest that you cut down the amount of driving at night in the dark to a minimum. The early morning seems to me to be the much better time. Possibly you can also ensure that driving in the dark is carried out on roads with a minimum amount of traffic. With reference to your loss of oil pressure after braking. If you dismantle the large oil pump you will find the bush that is pressed into the case has an annular clearance about 5 thou. wide between the brass and the aluminium. The large diameter bush is the one which causes the trouble. This groove short circuits the gear teeth and prevents the pump priming. If you fill it up with solder you should have no further trouble. I send you herewith a print with the groove marked, and will despatch a pump with the job done properly, by making the bush a tight fit, here, as soon as one is available. If you find the solder is satisfactory you might get Paris to do it on their demonstration cars. Rm.{William Robotham - Chief Engineer} | ||