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).
The temporary fitting of a general bypass filter to a Wraith III engine.
| Identifier | ExFiles\Box 135\3\ scan0156 | |
| Date | 8th July 1937 | |
| Sivdl Leveles Any commende SECRET. Par -BY.{R.W. Bailey - Chief Engineer} 1139 c. Rm.{William Robotham - Chief Engineer} c. HPS.{Horace Percy Smith - Experimental Factory Mgr} E/JNR.{Charles L. Jenner}1/HP.8.7.37. General Bypass Filter. -Wraith III Rm.{William Robotham - Chief Engineer} has expressed the desire to fit a bypass filter in place of the oil pressure filter when the car goes to France. We send you herewith LeC.5775 showing how this can be done in a temporary way to test its efficacy. It will be noticed that there are no alterations to the crankcase or cylinder, the bracket for carrying the filter being bolted to the existing face on the crankcase. There is no room to fit the hand ignition control so the vacuum operation will be necessary. The bypass filter is fed from the low pressure oil which supplies the rocker gear, the outlet from the filter being taken down to a union screwed into the amp plug. If the bypass filter does prove satisfactory then shortly we can provide for it properly on the engine, and delete the cross passage in the bottom of the sump, and thereby save some money. E/JNR.{Charles L. Jenner} | ||