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).
Oil pressure drop issues on chassis 3.B.IV and 6.B.IV.
| Identifier | ExFiles\Box 144\3\ scan0186 | |
| Date | 17th March 1937 | |
| 4113 1230 HOTEL DE FRANCE. CHATEAUROUX, Indre. France. Rm{William Robotham - Chief Engineer}/GWH{George W. Hancock - Head Chateauroux}/IMW{Ivan M. Waller - Head of Chateauroux}/4/JAB. 17th March 1937. To. Rm{William Robotham - Chief Engineer}/Gry.{Shadwell Grylls} c.c. Rm{William Robotham - Chief Engineer}/GWH.{George W. Hancock - Head Chateauroux} 3. B. IV. Further to our reply to your telegram re. Oil pressure drop, we confirm that at no time has the oil pressure on 3.B.IV. fallen on account of braking, but at the same time you will have seen from the reports that we haven't got much braking. Stretching the relief valve spring is not satisfactory. It does not remain stretched but gradually settles down. Also, it does not cure the falling off in oil pressure with really high oil temperatures. This latter trouble is not so noticeable on 6.B.IV. as it will not fall below say 35 lbs/sq", the normal pressure being above 40 lbs/sq" off the clock whereas, 3.B.IV falls to 23 lbs/sq" at maximum speed and below 20 lbs/sq" at 70 MPH. with oil temperature over 120°c. Rm{William Robotham - Chief Engineer}/GWH{George W. Hancock - Head Chateauroux}/IMW.{Ivan M. Waller - Head of Chateauroux} | ||