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).
Inspection report detailing the condition and wear of various engine components after mileage.
| Identifier | ExFiles\Box 82\3\ scan0360 | |
| Date | 4th June 1935 guessed | |
| ( 2 ) This was re-ground .003 " undersize. The main journal bearings white metal have started to break up, N° 2 and six bottom bearings and N° 7 top half of bearing. 5) NARROW PIN DRILLED UP CONNECTING RODS WITH STRIP LEAD BRONZE BEARINGS. Nos. 2, 3, & 6 bearing at this mileage were in a bad condition. N° 2, & 3 bottom shells were broken in two, top halves cracked across the centre, N° 6 the bottom half was cracked. N° 1 was still good. The shells of all the bearings, that had run the full mileage, had taken up a circle smaller than the Crankpin did. We are of the opinion that this has been caused by the continual hammering effect with a shortage of oil. The condition of the caps of the connecting rod bearings, distinctly show that not sufficent oil has been fed to them. The steel has been up to a temperature to cause the metal to turn blue. N° 3, and 4, are the worst, 2, and 5, a little less blue, 1, and 6, no colour showing that these two rods have received sufficient oil, but although the oil feed has been sufficient, the bearing was cracked on N° 6. N° 5 seized on the pin, causing the breaking of the retaining bolts. The result being the Crank hit the disconnected rod and knocked it through the case. The tabs holding the bearing in position were broken off. 6) TAXOLITE TIMING GEARS GROUND STEEL GEARS. The Gears have been 100% for quietness & freedom from rattle. They are still in a good condition. 7) LARGE HELICAL GEAR OIL PUMP. We have had no trouble with the Pump. The shortage of oil feed to the rods is due to design and not the effeciency of the pump. 8) GEARED STARTER MOTOR. The Starter Motor has given no trouble throughout the mileage. The Engine has been revolved vigourously and quick starts made. The motor completed 500 seperate engagements irrespective of the daily engagements. 9) EXISTING BENTLEY DYNAMO WITH MODIFIED VOLTAGE CONTROL REGULATOR. The Dynamo is in a good condition. No failure of output has occurred during the mileage. At no time has there been a shortage of current supply from the Battery. Replenishment of water to the Battery during the total mileage has been 1.3 pints. | ||