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).
Car mileage test which resulted in a big-end failure, including temperature readings and engine inspection notes.
| Identifier | ExFiles\Box 83\1\ scan0322 | |
| Date | 6th January 1936 | |
| HOTEL DE FRANCE. CHATEAUROUX, Indre. France. GWH{George W. Hancock - Head Chateauroux}/I/JAB. 6th January 1936. To. Sg.{Arthur F. Sidgreaves - MD} O.{Mr Oldham} Hs.{Lord Ernest Hives - Chair} c. Rm.{William Robotham - Chief Engineer} 6. B. IV. Upon arrival at Châteauroux, the car was held up to make and fit a pan under the bottom half of the engine to hold lagging on to the bottom half. This was to endeavour to raise the oil temperature to as near as Summer conditions as possible. This job has been completed. The car resumed the mileage test this morning. A telephone message was received from P. Rose at 12 O'clock that he was a hundred miles away and a big-end had failed. The knock was not too bad and I instructed him to return at a slow speed and coast where possible. The following is the record of the run up to the time of failure. 167 miles were run up to breakfast time, average speed 48 MPH. Oil Temp. Air Temp. Water Temp. 102°c 4°c 77°c 110 4 75 Readings 112 4 75 97 5 75 taken 100 5 74 94 6 74 every 20 miles. 100 6 74 92 7 75 94 7 75 The engine revs had not exceeded 4,300 up to the first stop. After breakfast, a further 103 miles were run at reduced speed of 60-65 MPH owing to heavy rain. The readings were:- Oil Temp. Air Temp. Water Temp. 98°c 8°c 75°c 102 8 75 95 8 74 84 8 74 92 8 74 The oil pressure was 38 lbs at 90°c and at no time was there a failure of pressure. We dismantled the lower half as soon as the car returned, and found that the failure was on N° 6 connecting rod bearing. A portion of metal had seized on to the crank pin at both sides of the drilled oil hole and had torn the metal out of the bearing like a cutting tool, deep grooves ran right round the both halves of the bearing. | ||