Programme of test bed work for a Wraith III No.2 unit, focusing on oil leaks and supply distribution.
| Identifier | ExFiles\Box 155\2\ scan0121 | |
| Date | 3rd August 1937 | |
| To Rm. {William Robotham - Chief Engineer} from Rm {William Robotham - Chief Engineer} /Swdl. {Len H. Swindell} C. Rm {William Robotham - Chief Engineer} /Mths. {Reg Matthews} C. Rm {William Robotham - Chief Engineer} /CTS. {C. Trot Salt - Carburation} C. Rm {William Robotham - Chief Engineer} /Ed. {J. L. Edwards} PROGRAMME OF TEST BED WORK. Further to memo Rm {William Robotham - Chief Engineer} /Swdl. {Len H. Swindell} 15/AP.16.7.37 WRAITH III. No.2.UNIT. Unit as removed from 25.G.Vl. {V. Lewis / Mr Valentine} chassis, No.3. taking its place. The following urgent jobs to be carried out on this unit. (1) Investigate and endeavour to cure leak past rear main bearing into clutch pit. Results of the work on the early 25/30. to cure this leak to be following through on Wraith. Try also a breather connection between the rocker cover and the air silencer, checking crankcase back pressure in each case. The 15,000 mile car is leaking at this point and we are anxious to cure the trouble as soon as possible. (2) Complete initial distribution tests as carried out on No.3. unit and give preliminary report with recommendations. (3) Oil supply distribution. With a normal oil pressure setting of 30 lbs/sq.in. main and 5 lbs/sq.in rockers under the conditions of 100°C. temp. at 4000 R.P.M. check at what speed oil is fed to the timing gears. The oil to the valve gear particularly at the valve tip end appears excessive at any speed above idling. It should be possible to keep this down to a reasonable amount by placing a restrictive jet in the feed pipe to the rockers. This could be done by having a single small hole in banjo screw on the head as carried out for experiment on 33-MX. {John H Maddocks - Chief Proving Officer} When by the above, the supply to the rockers is kept down to a reasonable amount, recheck the speed at which the gears are fed with oil. continued | ||
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).