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).
Test procedures and modifications for Wraith III and PH.III engine units.
| Identifier | ExFiles\Box 155\2\ scan0172 | |
| Date | 10th November 1937 | |
| -2- WRAITH III NO.8 UNIT continued. Take power curve open exhaust and with silencer. Fit Exs.312 and 313 valve spring and spring damper in which scheme the bottom washers are deleted. Following the above special jobs unit to be finalled off preparatory to fitting in chassis. WRAITH III NO.2 UNIT. Is being assembled for exhaust valve and bearing endurance. NO.5 TEST HOUSE. PH.III NO.13 UNIT. This unit is fitted with the following special parts. Front, centre and rear bearings standard W/MT, inter- mediates and AC.6 alloy. Big ends with Hall's A.C.6 bushes on crankpin inner bearing and W/MT outside face. Up to date cylinder heads will be fitted. Following running in during which time check oiling to valve gear etc., Rm{William Robotham - Chief Engineer}/Std. to check cylinder heads for water temperatures. Check power curve open exhaust and with silencer. In order to give cylinder heads a severe test, do several starts from cold, warm up quickly and cool down again. Run 1 hour at Bentley endurance speeds at an oil inlet temperature of 100°C and repeat. Final off unit with a view to fitting in chassis. | ||